... snip ...
Yahoo releases internet standard draft for using DNS as public key server
From: Lynn Wheeler
Date: 05/19/2004 09:26 PM
To: internet-payments@xxxxxxxx
Subject: Yahoo releases internet standard draft for using DNS as public key server
yahoo draft internet standard for using DNS as a public key server
http://web.archive.org/web/20040607200622/http://www.ietf.org/internet-drafts/draft-delany-domainkeys-base-00.txt
misc past news refs:
http://docs.yahoo.com/docs/pr/release1143.html
http://blogs.ittoolbox.com/linux/technologist/archives/000241.asp
http://web.archive.org/web/20040215184953/http://www.computerweekly.com/Article127082.htm
http://zdnet.com.com/2100-1104_2-5164279.html
http://www.ecommercetimes.com/perl/story/32995.html
a few past threads on using DNS as a public key server
http://www.garlic.com/~lynn/aadsmore.htm#pkiart2 Public Key Infrastructure: An Artifact...
http://www.garlic.com/~lynn/aepay4.htm#comcert2 Merchant Comfort Certificates
http://www.garlic.com/~lynn/aepay4.htm#comcert4 Merchant Comfort Certificates
http://www.garlic.com/~lynn/aepay6.htm#gaopki4 GAO: Government faces obstacles in PKI security adoption
http://www.garlic.com/~lynn/aadsm8.htm#softpki2 Software for PKI
http://www.garlic.com/~lynn/aadsm8.htm#softpki10 Software for PKI
http://www.garlic.com/~lynn/aadsm8.htm#softpki11 Software for PKI
http://www.garlic.com/~lynn/aadsm8.htm#softpki12 Software for PKI
http://www.garlic.com/~lynn/aadsm8.htm#softpki14 DNSSEC (RE: Software for PKI)
http://www.garlic.com/~lynn/aadsm8.htm#softpki16 DNSSEC (RE: Software for PKI)
http://www.garlic.com/~lynn/aadsm9.htm#cfppki5 CFP: PKI research workshop
http://www.garlic.com/~lynn/aadsm15.htm#28 SSL, client certs, and MITM (was WYTM?)
http://www.garlic.com/~lynn/aepay10.htm#31 some certification & authentication landscape summary from recent threads
http://www.garlic.com/~lynn/aepay10.htm#81 SSL certs & baby steps
http://www.garlic.com/~lynn/aepay10.htm#82 SSL certs & baby steps (addenda)
http://www.garlic.com/~lynn/aepay11.htm#37 Who's afraid of Mallory Wolf?
http://www.garlic.com/~lynn/2000e.html#40 Why trust root CAs ?
http://www.garlic.com/~lynn/2001c.html#8 Server authentication
http://www.garlic.com/~lynn/2001c.html#9 Server authentication
http://www.garlic.com/~lynn/2001d.html#36 solicit advice on purchase of digital certificate
http://www.garlic.com/~lynn/2001d.html#41 solicit advice on purchase of digital certificate
http://www.garlic.com/~lynn/2001e.html#26 Can I create my own SSL key?
http://www.garlic.com/~lynn/2001e.html#40 Can I create my own SSL key?
http://www.garlic.com/~lynn/2001e.html#46 Can I create my own SSL key?
http://www.garlic.com/~lynn/2001g.html#2 Root certificates
http://www.garlic.com/~lynn/2001g.html#19 Root certificates
http://www.garlic.com/~lynn/2001h.html#3 PKI/Digital signature doesn't work
http://www.garlic.com/~lynn/2001m.html#37 CA Certificate Built Into Browser Confuse Me
http://www.garlic.com/~lynn/2001n.html#57 Certificate Authentication Issues in IE and Verisign
http://www.garlic.com/~lynn/2002e.html#56 PKI and Relying Parties
http://www.garlic.com/~lynn/2002m.html#64 SSL certificate modification
http://www.garlic.com/~lynn/2002m.html#65 SSL certificate modification
http://www.garlic.com/~lynn/2002p.html#18 Cirtificate Authorities 'CAs', how curruptable are they to
http://www.garlic.com/~lynn/2002p.html#19 Cirtificate Authorities 'CAs', how curruptable are they to
http://www.garlic.com/~lynn/2003l.html#36 Proposal for a new PKI model (At least I hope it's new)
http://www.garlic.com/~lynn/2003l.html#43 Proposal for a new PKI model (At least I hope it's new)
http://www.garlic.com/~lynn/2003l.html#51 Proposal for a new PKI model (At least I hope it's new)
http://www.garlic.com/~lynn/2003l.html#53 Proposal for a new PKI model (At least I hope it's new)
http://www.garlic.com/~lynn/2003l.html#60 Proposal for a new PKI model (At least I hope it's new)
--
Internet trivia, 20th anv: http://www.garlic.com/~lynn/rfcietff.htm
Moving forward with pre-shared keys
From: Lynn Wheeler
Date: 05/20/2004 10:07 AM
To: "Joseph Salowey" <jsalowey@xxxxxxxx>
cc: "'Eric Rescorla'" <ekr@xxxxxxxx>, hzhou@xxxxxxxx, ietf-tls@xxxxxxxx,
"'David A. McGrew'" <mcgrew@xxxxxxxx>,
"'Nancy Cam-Winget'" <ncamwing@xxxxxxxx>
Subject: RE: Moving forward with pre-shared keys
similar ... but different ... is pre-stored keys .... the yahoo draft
that showed up yesterday to use DNS as a public-key server.
minor reference:
http://www.garlic.com/~lynn/aadsm17.htm#36
Study: ID theft usually an inside job
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From: Lynn Wheeler
Date: 05/22/2004 09:16 AM
To: internet-payments@xxxxxxxx
Subject: Study: ID theft usually an inside job
Study: ID theft usually an inside job
http://www.msnbc.msn.com/id/5015565
Up to 70 percent of cases start with employee heist
By Bob Sullivan
Technology correspondent
MSNBC
Updated: 7:03 p.m. ET May 21, 2004
A soon-to-be-released study reveals what some identity theft experts
have hinted at for years -- the crime is largely the work of
insiders. In a study of more then 1,000 identity theft arrests in the
United States, Michigan State professor Judith Collins has discovered
that perhaps as much as 70 percent of all identity theft starts with
theft of personal data from a company by an employee.
... snip ...
this isn't inconsistent with earlier studies claiming that general
fraud tended to be 90 percent insiders.
posting related to internet payments ... and security proportional to
risk
http://www.garlic.com/~lynn/2001h.html#61
part of the issue is the excessive amount of identity &/or static
shared-secret information laying about in authentication
infrastructures .... making the infrastructure vulnerable to identity
theft, or other kinds of impersonation and/or replay attacks.
The future of security
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Wed, 26 May 2004 09:51:01 -0600
To: "Steven M. Bellovin" <smb@xxxxxxxx>
Subject: Re: The future of security
Cc: Ian Grigg <iang@xxxxxxxx>,
Graeme Burnett <rgb@xxxxxxxx>, cryptography@xxxxxxxx
At 09:36 AM 5/11/2004, Steven M. Bellovin wrote:
In message <409ACFC7.6050407@xxxxxxxx>, Ian Grigg writes:
>
>Security architects
>will continue to do most of their work with
>little or no crypto.
And rightly so, since most security problems have nothing to do with
the absence of crypto.
>
>j. a cryptographic solution for spam and
>viruses won't be found.
This ties into the same thing: spam is *unwanted* email, but it's not
*unauthorized*. Crypto can help with the latter, but only if you can
define who is in the authorized set of senders. That's not feasible
for most people.
one of the issues has been that many crypto security solutions have
been oriented towards hiding information. that may work with outsiders
... but traditionally, 90percent of fraud has been insiders ... and
recent news last friday about study to be published was that
interviewing something like 1000 people involved in identity theft
cases ... it was determined that at least 70percent had some sort of
employee involvement.
in that sense ... the internet and introduction of the possibility of
outsider related fraud ... has distracted/obfuscating focus from the
real, long standing issues.
my repeated observation that current generation of desktop systems
were originally introduced to operate in a standalone environment
where applications could be introduced that freely took over the whole
machine. attempting to continue to satisfy the standalone ... total
take-over requirements at the same time using the same platform for
generalized interconnect to an increasingly hostile environment
creates some diametrically opposing objectives.
The future of security
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Fri, 28 May 2004 10:44:17 -0600
To: pgut001@xxxxxxxx (Peter Gutmann)
Cc: astiglic@xxxxxxxx, iang@xxxxxxxx,
smb@xxxxxxxx, cryptography@xxxxxxxx, rgb@xxxxxxxx
Subject: Re: The future of security
At 09:27 AM 5/28/2004, Peter Gutmann wrote:
No they won't. All the ones I've seen are some variant on the "build a big
wall around the Internet and only let the good guys in", which will never work
because the Internet doesn't contain any definable inside and outside, only
800 million Manchurian candidates waiting to activate. For example
MessageLabs recently reported that *two thirds* of all the spam it blocks is
from infected PCs, with much of it coming from ADSL/cable modem IP pools.
Given that these "spammers" are legitimate users, no amount of crypto will
solve the problem. I did a talk on this recently where I claimed that various
protocols designed to enforce this (Designated Mailers Protocol, Reverse Mail
Exchanger, Sender Permitted From, etc etc) will buy at most 6-12 months, and
the only dissent was from an anti-virus researcher who said it'd buy weeks and
not months. The alternative proof-of-resource-consumption is little better,
since it's not the spammers' resources that are being consumed.
the caveat to that is many of the infected machines were originally
infected by spam with spoofed origin ... somehow convincing users to
click on something. authentication would help somewhat with that
... and, in fact, some of the spam being sent out by the infected
machines, in turn uses spoofed origin. authentication might also help
address the identity-theft oriented spam ... claiming to be your bank
and needing personal information.
it doesn't help with ... click on this to get the latest, greatest
game ... where there isn't any attention at all paid to the origin
... just looking for instant gratification.
the 60s/70s time-sharing systems nominally had some assurance applied
to the introduction of executables into the environment. this is my
comment about the desktop systems having diametrically opposing
requirements ... the original design point of totally unconnected,
stand alone environment where an introduced executable could take over
the whole machine ... and at the same time fully wired to an
increasingly hostile environment needing signficant safeguards and
processes associated with assurance of introduced executables. the
intermediate step was that some of these stand-alone machines acquired
interconnect capability for a local, safe, isolated
departmental/office network. This had hardly any restricted execution
and access capability ... again not worrying about protection against
a hostile and unsafe operation.
the shared environment analogy is highway traffic and rules about
operating an unsafe vehicle could result in both having your license
revoked and the vehicle confiscated (it doesn't require the driver to
be a highly trained car mechanic ... it just holds the driver
responsible).
connecting systems that were designed for fundamentally safe and
isolated environment to wide-open anarchy hostile operation exposes
all sorts of problems. somewhat analogous to not actually needing a
helmet for riding a motorcycle ... or seat belts and airbags to drive
a car.
Yahoo releases internet standard draft for using DNS as public key server
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Tue, 01 Jun 2004 12:06:00 -0600
To: pgut001@xxxxxxxx (Peter Gutmann)
Cc: cryptography@xxxxxxxx, nelson@xxxxxxxx
Subject: Re: Yahoo releases internet standard draft for using DNS as public key server
At 10:14 PM 5/30/2004, Peter Gutmann wrote:
The S/MIME list debated this some time ago, and decided (pretty much
unanimously) against it, for two reasosn. Firstly, because it adds
huge ugly blobs of base64 crap to each message (and before the ECC
fans leap in here, that still adds small ugly blobs of base64 crap to
each message). Secondly, because if you get a message from someone
you know you'll be able to get a pretty good idea of its authenticity
from the content (for example an SSH developer would be unlikely to be
advocating SSL in a list posting), and if you get a message from
someone you don't know then it's pretty much irrelevant whether it's
signed or not. So the consensus was not to sign messages.
this may or may not be my KISS authentication thread.
mid-90s, some number of financial institutions retrenched from x.509
identity certificates to simple relying-party-only certificates
... because of enormous privacy issues regarding blanketing the world
with privacy information contained in identity certificates.
however, they were still looking at taking a 60-80 bytes payment
message, attaching a 128byte digital signature, and then attaching a
4k byte to 12k byte relying-party-only certificate ... and sending it
back to the financial institution that issued the certificate. this is
not counting any ASN.1 encoding that might have been done which then
possiby includes a bunch more bytes. note that standard payment
message message has been around some 30 years carefully crafted as
simple 7bit ascii w/o any addition encoding requirements. the purpose
of the certificate was to carry the account number ... which was also
included in the signed payment message ... and the public key
... which was stored in the account record back at the financial
institution that was receiving the transmission and had originally
issued the relying-party-only certificate.
so the financial institution receives this new payment object,
retrieves the account number from the (signed) payment message and
uses the public key in the account record to verify the signature
... w/o ever resorting to the certificate. So we have a payload bloat
of one hundred times ... in order to carry a certificate that is
redundant and superfluous and never used.
so x9.59 was fairly carefully crafted to add a 42byte ECC signature to
a standard 60-80byte payment message. any special encoding to carry
42byte ecc 8bit in 7bit transmission at worst doubled the signature
payload size.
http://www.garlic.com/~lynn/x959.html#x959
Article on passwords in Wired News
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Sun, 06 Jun 2004 13:54:01 -0600
To: Ernst Lippe <ernstl@xxxxxxxx>
Subject: Re: Article on passwords in Wired News
Cc: martin f krafft <madduck@xxxxxxxx>, cryptography@xxxxxxxx
At 02:19 AM 6/5/2004, Ernst Lippe wrote:
What is that card? There are some schemes that use debit cards
with an embedded smartcard. If you are referring to one of these
schemes I don't think that they are more secure than TAN's. If
it is a card that you carry along with you, the risk that it will
be stolen is higher than the risk that some TAN's will be stolen,
because in most cases you are able to store your TAN's in
a safe place in your home. The only apparent advantage of
using a card is the PIN, i.e. something you know, but all
internet banking application that I have seen require some form
of password which has at least the same security as a PIN.
If it really is a debit card, then the security is probably
even worse. In several debit card schemes the PIN for cash
transactions is the same as the PIN for web transactions (
if the users have the possibility to change either PIN, it
is a safe bet that they will be both the same), and it it not
at all difficult to determine the PIN in this case.
there is two factor authentication:
• something you have
• something you know
in this scenario we could conclude there are are a least
3-4 types of something you know authentication.
• re-usable shared-secret, things like run-of-the-mill
account numbers .. where knowing the account number is
sufficient to perform a fraudulent transaction. these are
extremely attractive to criminals ... because merchants
tend to aggregate them in transaction files ... so a single
theft of the transaction file could represent an extremely
huge return-on-investment (benefit/risk trade-off). some past
discussion of this with regard to security proportional
to risk:
http://www.garlic.com/~lynn/2001h.html#61
• shared-secret, one-time account numbers. this is
a fairly adequate countermeasure for the major fraud
scenario ... harvesting merchant account files. there
can still thefts/copying of individual account sheets,
just like there can be thefts of individual cards. note
however that the benefit/risk of individual thefts is
orders of magnitude less than the merchant transaction
file harvesting. as per the above url discussion of
security vis-a-vis risk ... harvesting a merchant account
file of re-usable account numbers may represent a $50m
exposure ... and hundreds of thousands of dollars
expense to a bank to block the affected accounts and
re-issue new cards. one time numbers may represent
little or no countermeasure to the individual vulnerability
.... but it represents a countermeasure for the aggregate
vulnerability that is several orders of magnitude larger
and more expensive
• something you have cards ... that are supposedly
hard to counterfeit ... but changing technology over
the years have made them more and more vulnerable,
PINs with most of these existing cards have been
somewhat something you know shared-secret ...
i.e. some flavor of it is transmitted to the financial
institution. skimming technology captures the
magstripe value as well as the entered PIN;
counterfeit cards are then manufactured ... along
with notation regarding the correct pin. this
skimming also relies on re-usable values ... and
skimming operations can be setup and automated
to capture tens of thousands
• newer generation of something you have cards
with embedded chips and non-shared-secret
PINs ... i.e. the correct PIN has to be sent
to the chip ... before the chip performs the
correct operation. Some of these have acquired
the yes card label in some parts of euro-press.
transaction information is skimmed ... sufficient
to create a counterfeit chip-card. these counterfeit
chip-cards answer YES to everything ... i.e.
whether the pin entered was correct, whether the
transaction value is less than limit, etc. again
the skimming process has been automated,
allowing the capture of information for potentially
thousands of counterfeit cards (the skimming
can be identical to that used with magstripe cards).
Is finding security holes a good idea?
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Wed, 16 Jun 2004 09:57:08 -0600
To: "Arnold G. Reinhold" <reinhold@xxxxxxxx>
Subject: Re: Is finding security holes a good idea?
Cc: "Steven M. Bellovin" <smb@xxxxxxxx>,
Ben Laurie <ben@xxxxxxxx>,
Eric Rescorla <ekr@xxxxxxxx>, cryptography@xxxxxxxx
At 10:14 PM 6/15/2004, Arnold G. Reinhold wrote:
"The Mythical Man-Month" is a great book, but it's almost 30 years
old. Brooks considered OS/360 to be hopelessly bloated. My favorite
quote (from Chapter 5, The Second System Effect, p. 56):
"For example, OS/360 devotes 26 bytes of the permanently resident
date-turnover routine to the proper handling of December 31 on leap
years (when it is Day 366). That might have been left to the
operator."
Modern operating system are 2 to 3 orders of magnitude larger than
OS/360.. They are far more reliable than OS/360 was in its early days
and do not presume the availability of an on-site team of operators
and system programmers. For the most part they are still maintained
one bug at a time The bug fixing process has not reached Brook's
predicted crisis.
a small joke where we would rib the mvs people that the 40k byte
os/360 simulator in cms did almost as good a job as the 8mbyte plus )
os/360 simulator in MVS (i.e. kernel reserved 8mbytes of the virtual
address space, there was also a whole bunch of non-resident
stuff). recent thread in comp.arch:
http://www.garlic.com/~lynn/2004f.html#55 Infiniband - practicalities for small clusters
references to environment in the disk engineering lab with "testcells"
which resulted in 15min MTBF for MVS with single test cell operating
... and therefor required that single testcell (at a time) development
& test occured in stand-alone environment. I rewrote the I/O subsystem
so that six to 12 testcells could be operated concurrently in an
online environment:
http://www.garlic.com/~lynn/subtopic.html#disk
there are several feedback effects to controlling bug process
.... when bugs get to bad ... the users, customers, installations stop
doing the things that hurt (the joke about guy going to the doctor and
saying it hurts when i do this ... and the doctor says stop doing
it). the other effect is that when the backlog of bugs get too long
... everybody gets pulled off everything else and the only thing that
goes on is bug fixes.
finally, there has been fairly stringent change control and regression
testing evolved at all stages in the infrastructure ... if the new
changes can't do all the work that the unchanged system could ... then
the changes aren't rolled in. For large, complex infrastructures, this
has a tendency limiting change. One might conclude that was one of the
reasons that the whole future system failed in the early 70s which was
going to be a much more radical change than 360 had been before it. In
a seminar at MIT in the early 70s, Amdahl sort of alluded to this as
being one of the arguments that he used to get funding for his new
company.
the supposed justification for FS (future system) project was
countermeasure to the PCM controller business ... something that I've
beenaccused as helping originate from a project that I worked on as an
undergraduate ... supposedly producing the first PCM controller
(i.e. reverse engineered 360 channel interface, built channel board
and programmed a minicomputer to emualte a 360 controller)
http://www.garlic.com/~lynn/subtopic.html#360pcm
specific reference to fs overview
http://www.garlic.com/~lynn/2000f.html#16 [OT] FS - IBM Future System
lots more references to future systems
http://www.garlic.com/~lynn/submain.html#futuresys
if you are really feeling interested ... when I did the resource
manager ... I did a series of 2000 tests that took three months
elapsed time beofre release the product ... misc. past refs to
regression testing & benchmarking procedure:
http://www.garlic.com/~lynn/submain.html#bench
the base product had a process that released a monthly accumulated fix
(PLC) tape. They wanted me to provide a monthly resource manager PLC
tape on the same schedule .... however, I said that it would be nearly
impossible for me to do it more than once every three months since at
a minimum I would have to do at least 100 different regressions tests
taking minimum of 48 hrs elapsed time for even an incremental PLC
distribution. resent posting about the whole PLC business
http://www.garlic.com/~lynn/2004g.html#40 IBM 7094 Emulator - An historic moment?
lots of past posts about resource manager, scheduling, page
replacement algorithms, caching, etc:
http://www.garlic.com/~lynn/subtopic.html#fairshare
http://www.garlic.com/~lynn/subtopic.html#wsclock
Is finding security holes a good idea?
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Wed, 16 Jun 2004 10:24:33 -0600
To: "Arnold G. Reinhold" <reinhold@xxxxxxxx>
Subject: Re: Is finding security holes a good idea?
Cc: "Steven M. Bellovin" <smb@xxxxxxxx>,
Ben Laurie <ben@xxxxxxxx>,
Eric Rescorla <ekr@xxxxxxxx>, cryptography@xxxxxxxx
oh, and almost forgot ... a rambling story that gets around to talking
about future system project ... and all the super security that they
put in place to protect all the future system documentation ... they
really wanted to have an environment where the future system
documentation was only available in restricted online, softcopy
environment and it was impossible to get hardcopy (this was somewhat
after a incident were paper document of unannounced 370 virtual memory
was "copied" and leaked to the press ... which led to putting
embossing numbers on all copy machines which would show up on all
copies). somebody made the off-hand statement that even I couldn't
access the documents .... so i replied i could do it in less than five
minutes (... actually 60 seconds ... but i first had to remove all
connections to the machine because what i was going to do was really
fundamental).
http://www.garlic.com/~lynn/2004g.html#45 command line switches [Re: [REALLY OT!] Overuse of symbolic constants]
x9.99 financial PIA standard now available from ANSI e-store
From: Lynn Wheeler
Date: 06/18/2004 08:51 AM
To: internet-payments@xxxxxxxx
Subject: x9.99 financial PIA standard now available from ANSI e-store
somewhat in conjunction with working on X9.99, i started a merged
financial privacy taxonomy and glossary. for more notes & pointers on
merged taxonomy & glossary work see:
http://www.garlic.com/~lynn/index.html#glosnote
x9.99 at the ansi e-store
ANSI X9.99
authentication and authorization (was: Question on the state of the security industry)
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Thu, 01 Jul 2004 20:40:39 -0600
To: John Denker <jsd@xxxxxxxx>
Subject: Re: authentication and authorization (was: Question on the state of the security industry)
Cc: cryptography@xxxxxxxx, Ian Grigg <iang@xxxxxxxx>
At 12:26 PM 7/1/2004, John Denker wrote:
The object of phishing is to perpetrate so-called "identity
theft", so I must begin by objecting to that concept on two
different grounds.
there are two sides of this .... some amount of crime statistics call
it ID-theft .... which plausibly could be either identity or
identification ... but in general involves situation where criminal is
impersonating you to one degree or another to perform some fraudulent
action.
there has been some attempt to distinguish impersonation events
between fraudulently extracting money from existing accounts and
fraudulently creating new accounts in your name.
practically, objecting to the label id-theft may be like objecting to
the label suicide bomber.
in general, the problem is using any kind of static data for
authentication. it applies to name, birthdate, mother's maiden name,
pins, passwords, account numbers .... any kind of static data. it
worked for a long time ... but it was based on assumption that it had
characteristics of 1) shared-secret and 2) used uniquely, different
static data in different security domains.
the growth of electronic environments has drastically affected this in
lots of ways (invalidating the core assumptions that was behind the
use of such static data for authentication, it wasn't that static data
didn't work ... but it worked well only as long as the underlying
assumptions were valid):
1) drastic increase in number of different electronic environments
requiring unique shared-secrets ..... basic human factors making it
impossible to process unique shared-secret for every possible (scores
of unique) environment
2) drastic increase in number of different electronic environments
... drastically increasing the number of places that shared-secrets
are being used ... which increasing the places that shared-secrets can
be harvested (for criminal purposes)
3) drastic increase in electronic environments that contain
information about individuals ... drastically increasing the number of
places that personal information can be harvested (of the type that is
likely to be used in shared-secret, static authentication information)
for criminal purposes.
minor reference to the account based scenario .... security proportional to risk
http://www.garlic.com/~lynn/2001h.html#61
and then there is the whole thing about frequent confusion of
identification and authentication:
http://www.garlic.com/~lynn/aepay3.htm#mcomm (my) misc. additional comments on X9.59 issues.
http://www.garlic.com/~lynn/aepay7.htm#3dsecure 3D Secure Vulnerabilities? Photo ID's and Payment Infrastructure
http://www.garlic.com/~lynn/aadsm9.htm#pkcs12b A PKI Question: PKCS11-> PKCS12
http://www.garlic.com/~lynn/aadsm14.htm#40 The real problem that https has conspicuously failed to fix
http://www.garlic.com/~lynn/aadsm14.htm#41 certificates & the alternative view
http://www.garlic.com/~lynn/aadsm17.htm#13 A combined EMV and ID card
http://www.garlic.com/~lynn/aadsm17.htm#16 PKI International Consortium
http://www.garlic.com/~lynn/aepay11.htm#66 Confusing Authentication and Identiification?
http://www.garlic.com/~lynn/aepay11.htm#72 Account Numbers. Was: Confusing Authentication and Identiification? (addenda)
http://www.garlic.com/~lynn/aepay11.htm#73 Account Numbers. Was: Confusing Authentication and Identiification? (addenda)
http://www.garlic.com/~lynn/2003j.html#47 The Tao Of Backup: End of postings
authentication and authorization ... addenda
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Fri, 02 Jul 2004 07:57:02 -0600
To: cryptography@xxxxxxxx
Subject: Re: authentication and authorization ... addenda
ref:
http://www.garlic.com/~lynn/aadsm17.htm#46
one of the industry groups brought my wife and me in to help work on
the cal. and then the federal e-sign legislation. there is this
intersection between privacy, e-sign, and fraud. in any case, one of
the things that they had done was a study of the driving factors for
legislative and regulatory privacy activity ... the two primary
driving factors were
• id-theft
• (institutional) denial of service (to individuals)
the claim could be made that the id-theft issue is almost totally
related to the use of various kinds of static data for authentication
and that given the current pervasive electronic online world .... that
it is effectively impossible to continue operating with static data
paradigm w/o having to accept large amount of exploits and fraud.
the privacy legislative and regulatory mandates can try and establish
rules for "protecting" information ... but keeping static data
authentication information "private" is a loosing battle. in part,
because traditionally 90% of the exploits have involved insiders
.... although recent study now only claims that at least 77% of the
incidents involve insiders. All the internet histeria about outsiders
... in part just obfuscates identifying the real sources of the
problem.
one assertion is that the whole environment collapses because large
scale, wide-spread static data based authentication paradigm has too
many vulnerabilities ... somewhat as per the previous reference to
security proportional to risk
http://www.garlic.com/~lynn/2001h.html#61
if nothing else ... there isn't sufficient finances to fund the
security necessary to protect all the authentication static
data. also, this isn't taking into account the wide-spread education
necessary for countermeasure to the social engineering and phishing
exploits.
some sort of hardware token with non-static data (as something you
have authentication) starts to address the situation. the issue isn't
that the hardware token can't be stolen .... but it is difficult to
steal electronically a million at a time (large scale harvesting with
little investment and risk is one of the things that makes phshing so
attractive ... the potential fraud ROI is enormous).
If the hardware token implements a non-static data authentication
paradigm and never exposes its internal secrets (say like a private
key of public/private key pair) ... then no amount of phishing can
convince somebody to divulge something that they don't know. social
engineering might still be able to convince people to mail their
authentication token to some far off country (that requires quite a
bit more gullable populace .... comparable to convincing everybody
that they have to mail off their driver's license to some far off
location).
changing the paradigm from static data authentication to non-static
data authentication would do more for reducing id-theft
vulnerabilities than all the privacy and security regulations. one of
the side issues .... is sometimes if all you have is a data security
classification & protection hammer ... then the solution to all
problems is protecting the data. The security proportional to risk
scenario is it is impossible to protect the pervasive use of
authentication static data ... the paradigm has to be changed.
legislative and regulatory privacy mandates would still be necessary
for the other privacy driving factor .... (institutional) denial of
service (to individuals).
there will still be various kinds of impersonation fraud .... if you
can't perform fraudulent financial transactions by stealing account
numbers .... criminals might still open accounts in victims
names. However, an assertion is if the points of attack are reduced by
several orders of magnitude ... aka from all transactions (because of
stolen account numbers) to stolen hardware tokens and opening accounts
... then it is possible to better concentrate the security budget on
the drastically reduced attack points and threat models.
i mentioned before that i've been one of the x9.99 (privacy impact
assessment) standard co-authors for the last year or so .... and it is
now out for public comment (can be bought from the ansi e-store)
... and there is work item proposal to move it forward to ISO. For
part of the background work, i started a merged privacy taxonomy and
glossary .... similar to the merged taxonomy & glossary work that i've
done in other areas:
http://www.garlic.com/~lynn/index.html#glosnote
FTC has some resources in this area:
http://www.ftc.gov/bcp/conline/edcams/gettingcredit/resources.html
I gave a talk earlier this week at treasury conference in DC on
privacy and id-theft ... and there were some number of questions about
resources for individuals that are victims of id-theft
Japanese bank offers 'biosecurity' account
From: Lynn Wheeler
Date: 07/02/2004 12:58 PM
To: internet-payments@xxxxxxxx
Subject: Japanese bank offers 'biosecurity' account
http://web.archive.org/web/20040910000733/http://www.kansascity.com/mld/kansascity/business/technology/9066667.htm?1c
TOKYO (AP) - A Japanese bank on Friday launched a biosecurity account,
the holders of which can only conduct transactions once they have
proved their identity -- by showing the pattern of veins on their
palms.
... snip ...
slightly related to id-theft & authentication thread in another mailing list:
http://www.garlic.com/~lynn/aadsm17.htm#46 authentication and authorization (was: Question on the state of the security industry)
http://www.garlic.com/~lynn/aadsm17.htm#47 authentication and authorization ... addenda
--
Internet trivia, 20th anv: http://www.garlic.com/~lynn/rfcietff.htm
Use cash machines as little as possible
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Sun, 04 Jul 2004 14:25:23 -0600
To: cryptography@xxxxxxxx
Subject: Use cash machines as little as possible
http://www.thisislondon.com/news/business/articles/timid80044?source=
http://www.thisismoney.com/20040704/nm80044.html
ONE of Britain's biggest banks is asking customers to use cash
machines as little as possible to help combat soaring card fraud.
... snip ..
authentication and authorization (was: Question on the state of the security industry)
Refed: **, - **, - **, - **, - **, - **, - **
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Wed, 07 Jul 2004 10:07:29 -0600
To: "Anton Stiglic" <astiglic@xxxxxxxx>
Subject: RE: authentication and authorization (was: Question on the state of the security industry)
Cc: "'John Denker'" <jsd@xxxxxxxx>,
<cryptography@xxxxxxxx>, "'Ian Grigg'" <iang@xxxxxxxx>
At 07:23 AM 7/5/2004, Anton Stiglic wrote:
Identity has many meanings. In a typical dictionary you will find
several definitions for the word identity. When we are talking about
information systems, we usually talk about a digital identity, which
has other meanings as well. If you are in the field of psychology,
philosophy, or computer science, identity won't mean the same
thing. One definition that relates to computer science that I like is
the following: "the individual characteristics by which a thing or
person is recognized or known".
another way of looking at it in an authentication/authorization
infrastructure is that some set of privileges are asserted ... this is
typically done by having some sort of identification associated with
those privileges (like an account number or userid). There can be some
confusion whether what is being asserted is a tag, identity or
identification. if the tag being asserted, is something like a
person's name, the institution is likely just using it for a tag to
look up the set of privileges associated with that name (they may not
actually care who you are ... they want to know what privileges are
associated with the name/tag).
then there is some sort of authentication as to the binding to those
set of privileges .... aka 3-factor authentication taxonomy
• something you know
• something you have
• something you are
note, in some scenarios .... it is possible that knowing the account
number provides both the privilege assertion as well as the something
you know authentication (aka knowing the account number is sufficient
to make withdrawals).
in any case there are frequently used institutional processes that can
be characterized by assertion of privileges and authentication. The
taxonomy of those processes can be considered independent of the terms
used to label the processes (is a guard really interested in who you
are or just finding out what privileges and permissions you have).
so we have an environment with institutions and CSOs and an attitude
that the institution and the institution integrity must be protected
from outsiders (and criminal insiders)
however, with the prevalent use of static data and something you
know authentication paradigms ... there is huge amounts of static
data laying around, ripe for the harvesting ... where the criminal
impersonates an individual. so one view is that the vulnerability is
the extensive use by institutions of static data and something you
know authentication, where the individual may have little or no
ability to protect the majority of the information. The crime appears
to be against the individual and the source of the information may be
totally unrelated to where the crime actually occurs. Assuming that
the source of the vulnerability are the institutional infrastructures,
some laws have been passed to try and hold the institutions
responsible for the protection of individual information. in some
scenarios, institutions are charged with protecting individual
information from the institution itself (which sort of inverts a
security officers job of protecting institution from others).
However, in some scenarios
http://www.garlic.com/~lynn/2001h.html#61
the common use of static data is so pervasive that an individual's
information is found at thousands of institutions. The value of the
information to the criminal is that the same information can be used
to perpetrate fraud across all institutions and so the criminal value
is enormous. However the value to each individual institution may be
minimal. As a result there can be situations where an individual
institution hasn't the infrastructure or the funding to provide the
countermeasures necessary to keep the criminals away from the
information (they simply don't have the resources to provide security
proportional to the risk).
The value of the static data authentication information to a criminal
is far greater than the value of the information to the institution
... or the cost to the criminal to acquire the information is
possibly orders of magnitude less than the value of the information
(for criminal purposes).
Given such a situation .... the infrastructures simply don't have the
resources to provide the countermeasures adequate to meet the attacks
they are going to experience (there is such a huge mismatch between
the value of the information to the individual institutions and the
value of the information to the criminal).
Which results in my assertion that there has to be a drastic move away
from the existing static data authentication paradigm .... because
there is such a mismatch between the value to secure the information
verses the value of attacks to obtain the information.
It isn't that theory can't provide mechanisms to protect the
information .... it that the information is spread far and wide and is
in constant use by thousands of business processes, and that
protection problem is analogous to the problem of having people
memorize a hundred different 8+character passwords that change every
month (which is also a shortcoming of the static data authenticaton
paradigm).
misc:
http://www.garlic.com/~lynn/subintegrity.html#fraud
http://www.garlic.com/~lynn/subpubkey.html#privacy
authentication and authorization
Refed: **, - **, - **
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Wed, 07 Jul 2004 10:25:02 -0600
To: "Anton Stiglic" <astiglic@xxxxxxxx>
Subject: RE: authentication and authorization
Cc: "'John Denker'" <jsd@xxxxxxxx>,
<cryptography@xxxxxxxx>, "'Ian Grigg'" <iang@xxxxxxxx>
At 09:20 AM 7/6/2004, Anton Stiglic wrote:
Well, there is nt established technical definition for "digital
identity", but most definitions seem to focus to what I defined it as.
there is actually a whole series of issues.
the identity x.509 certificates from early 90s were targeted at stuff
that appeared to be totally unrelated to existing business processes
and environment.
given the scenario that existing business relationships and
permissions have been established .... there is requirement to
asserting access to those permissions (some means of asserting some
identification associated with the permissions and some means of
authentication or substantiating the rights to the permissions).
identity x.509 certificates have been totally unrelated to such a
business environment ... although attempts have been made to contort
them into that use. the original premise was that the identity x.509
certificates could be used by parties that previously had no direct
knowledge of each other and could make use of the x.509 certificates
w/o needing any recourse to any additional information. one problem
was a random name from some place in the world had no context or
meaning to some other random entity some place in the world.
putting a person's instantly changing available balance in the
certificate might do. however this had (at least) two problems 1) it
could be considered privileged information that deemed not advisable
in public certificates with copies all over the planet and 2) with
possibly thousands of each such certificate cached all around the
world .... there was some issue with instantaneously and dynamically
updating all copies.
so in the mid-90s there was some retrenchment to relying-party-only
certificates ... which basically only contained an account number and
the public key. the transaction always went to where the permissions
and other important information was available. However it was
trivially possible to show that in such situations, the certificates
are redundant and superfluous.
The majority of the business infrastructures in the world don't need
free floating and complete personal information contained in a
certificate about random and totally unknown entities. The need a
non-static-data authentication paradigm to replace the static data
authentication paradigm, i.e. simply replace pin/password with public
key and digital signatures.
misc:
http://www.garlic.com/~lynn/subintegrity.html#fraud
http://www.garlic.com/~lynn/subpubkey.html#privacy
FUJITSU DEVELOPS ENCRYPTION TECH THAT TAKES 20 MILLION YEARS TO BREAK
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Thu, 08 Jul 2004 08:33:42 -0600
To: <cryptography@xxxxxxxx>
Subject: FUJITSU DEVELOPS ENCRYPTION TECH THAT TAKES 20 MILLION YEARS TO BREAK
http://www.antaranews.net/en/index.php?id=s6384
Tokyo, July 8 (ANTARA/AFP) - Japanese IT giant Fujitsu Ltd. said
Wednesday it has developed credit card encryption technology which is
impossible to break with existing means
... snip ...
Using crypto against Phishing, Spoofing and Spamming
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Thu, 08 Jul 2004 09:44:52 -0600
To: hal@xxxxxxxx ("Hal Finney")
Subject: Re: Using crypto against Phishing, Spoofing and Spamming...
Cc: cryptography@xxxxxxxx
At 10:40 AM 7/7/2004, Hal Finney wrote:
SET failed due to the complexity of distributing the software and
setting up the credentials. I think another reason was the go-fast
atmosphere of the late 90s, where no one wanted to slow down the
growth of ecommerce. The path of least resistance was simply to bring
across the old way of authorizing transactions by card number.
both SET & SSL encrypted data in transit.
an issue is that SET is significantly more complex and provided no
additional countermeasure (vis-a-vis SSL) against major
remaining exploits .... like harvesting the merchant transaction file
while at rest.
there was some issue that SSL was the incumbent ... so SET had to
demonstrate significant better ROI to displace it ... rather than
significantly higher "I" with little or no additional "R".
some SSL:
http://www.garlic.com/~lynn/aadsm5.htm#asrn2
http://www.garlic.com/~lynn/aadsm5.htm#asrn3
the security proportional to risk reference (using merchant
transaction file as example)
http://www.garlic.com/~lynn/2001h.html#61
couple minor past refs related to SET business operations
http://www.garlic.com/~lynn/aepay7.htm#nonrep5 non-repudiation, was Re: crypto flaw in secure mail standards
http://www.garlic.com/~lynn/aepay7.htm#nonrep6 non-repudiation, was Re: crypto flaw in secure mail standards
another SET issue was that it took a typical ISO 8583 transaction of
60-80 bytes and added a RSA 128-byte digital signature and issuing
certificate of 4k-12k bytes .... effectively increasing the payload
size by a factor of two orders of magnitude. it stripped all the SET
overhead off at the internet boundary and transmitted a traditional
8583 message (in part because it was difficult to justify a 100-fold
increase in payload size for no obvious benefit) with a flag
indicating whether the signature had verified.
There was some presentation at an ISO meeting by one of the
association business people about the number of 8583 messages with the
signature-verified flag turned on and they absolutely knew that there
was no SET technology involved (some justification was association was
proposing rules that transactions with the flag on would have lower
merchant fees).
missing is that typical authorization includes a lot of dynamic and
aggregation factors (like credit limit) that are totally missing in a
simple stale, static certificate-based (offline) authentication
model. In fact, most infrastructures that involve transactions of any
value have migrated and/or are migrating to online infrastructures
that involve timely and/or aggregated information .... something that
is missing from a purely offline, certificate-based, stale,
static data infrastructure.
misc. implications
1) given an online transaction environment, it is then trivial to show
that certificates are redundant and superfluous ... because it is
possible to access the timely updated copy of the information rather
than having to rely on the stale, static copy of the certificate
information (designed to satisfy an offline environment requirement)
2) certificate market then becomes relegated to both offline and
no/low value (as infrastructures of value migrate to online paradigms)
3) there is little/no justification for paying money for certificates
if only no/low value infrastructures are involved.
4) w/o significant funding for certificate-based infrastructure, there
is little money to underwrite high-integrity certificate-based
operations
5) with no high-integrity certificate-based operations, it is
difficult to justify using certificates for high-value operations
6) go to #2
as has past frequently noted, the requirement given the x9a10 retail
payments working group for the x9.59 standard was to preserve the
integrity of the financial infrastructure for all retail payment
environments. one of the considerations was being able to accommodate
end-to-end integrity ... aka the financial responsible entity for
authorizing the transaction also performs the authentication. another
issue for x9a10 was to address other kinds of risks
.... like the merchant transaction file where the information
traditionally has to occur in the clear to support normal business
operations (offer something more than the encryption of data
in-flight).
http://www.garlic.com/~lynn/x959.html#x959
lots of posts about certificate infrastructures
http://www.garlic.com/~lynn/subpubkey.html#sslcerts
and relying-party-only certificates
http://www.garlic.com/~lynn/subpubkey.html#rpo
misc. stuff on x9.59, identity, authentication, and privacy
http://www.garlic.com/~lynn/subpubkey.html#x959
Using crypto against Phishing, Spoofing and Spamming
Refed: **, - **, - **, - **, - **, - **, - **, - **
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Fri, 09 Jul 2004 04:14:01 -0600
To: hal@xxxxxxxx ("Hal Finney")
Subject: Re: Using crypto against Phishing, Spoofing and Spamming...
Cc: cryptography@xxxxxxxx
At 10:40 AM 7/7/2004, Hal Finney wrote:
SET failed due to the complexity of distributing the software and setting
up the credentials. I think another reason was the go-fast atmosphere of
the late 90s, where no one wanted to slow down the growth of ecommerce.
The path of least resistance was simply to bring across the old way of
authorizing transactions by card number.
the other issue was rsa public key op overhead (besides extreme
payload bloat, extreme additional complexity, and no significant
countermeasures for prime exploits compared to e-commerce incumbent
SSL) ... ref: previous post:
http://www.garlic.com/~lynn/aadsm17.htm#53
when the initial set specification was published, i did a business
profile and a performance profile (including public key operations
profile). somebody i knew was playing with bsafe library and tweaked
it to run four times faster. I got him to run the SET public key op
profile on a number of processors.
i mentioned the numbers at some SET get together and the response from
the SET people was that it was 100 times too slow (if they had ever
run any bsafe they should have realized that it was four times too
fast). anyway ... sometime later when they had actual SET
implementations running ... the earlier profile numbers were within a
couple percent of measured on actual implementations.
i also observed that given nominal extended peak avgs. of
1000/transactions per sec .... that if SET ever actually became
mainstream operational (rather than just toy pilots) ... processing
would need something like 100,000 to 250,000 extra processors to
handle the RSA op processing load. the counter argument was that SET
would take so long to became mainstream ... that by then CPUs might be
ten to 100 times faster and it might only require 10,000 to 25,000 (or
1,000 to 2,500?) extra processors.
Using crypto against Phishing, Spoofing and Spamming
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Thu, 15 Jul 2004 09:06:42 -0600
To: Rich Salz <rsalz@xxxxxxxx>
Subject: Re: Using crypto against Phishing, Spoofing and Spamming...
Cc: Hal Finney <hal@xxxxxxxxx>,
<cryptography@xxxxxxxx>
At 06:42 AM 7/15/2004, Rich Salz wrote:
it wasn't a CCard transacdtion, my liability under SET was unlimited
(at least until Congress caught up to the technology). Looking at the
risk management aspect, SET was a big loser for the customer.
my earlier responses
http://www.garlic.com/~lynn/aadsm17.htm#53
http://www.garlic.com/~lynn/aadsm17.htm#54
i also included some discussion on it at a talk i gave on naked keys
at global grid forum conference last month, focusing on business
issues of authentication; ... minor ref (with pointer to the GGF pages
& presentation):
http://www.garlic.com/~lynn/2004g.html#53
with some comparison to x9.59
http://www.garlic.com/~lynn/x959.html#x959
.... one of the business issues with public key infrastructures is the
dual-use vulnerability of using digital signatures for both
authentication and signatures.
many of the authentication infrastructures have the server sending the
user some random data to be signed as part of authentication (issues
like replay attacks, etc); which the user never looks at.
ignoring all the non-repudiation issues .... real signatures are
suppose to imply things like agreement, approval, and/or authorization
(of the contents of what is being signed).
the dual-use vulnerability is ever having signed random data ... w/o
reading it .... and using the same technology to sign documents where
reading is implied (as well as agreement, approval, authorization).
the scenario is somewhat out of MASH where Radar is periodically
having the col. sign documents w/o having read them.
Question on the state of the security industry
Refed: **, - **, - **
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Thu, 15 Jul 2004 17:18:21 -0600
To: Ian Grigg <iang@xxxxxxxx>
Subject: Re: Question on the state of the security industry
Cc: cryptography@xxxxxxxx
A couple recent news stories
1)
Intuit warns of credit card risk
http://news.com.com/Intuit+warns+of+credit+card+risk/2100-1029_3-5269821.html
2)
Cyberattacks are soaring, countermeasures are sucking up tons of cash,
and hardware and software vendors for the most part are sitting it
out, *Bob Evans* says. But big customers are starting to say enough is
enough, so the business-technology world is about to get whirled.
http://www.informationweek.com/story/showArticle.jhtml;jsessionid=WK0LPHXYB4YSUQSNDBGCKHY?articleID=22104612
...................
i've been saying for some time that after market security is broken by
design ... it is somewhat like after market seat belts of the 60s. for
security to work, it has to be designed & built in from the start
.... some relatively recent comments about after market security:
http://www.garlic.com/~lynn/2002h.html#39 Oh, here's an interesting paper
http://www.garlic.com/~lynn/2002p.html#27 Secure you PC or get kicked off the net?
http://www.garlic.com/~lynn/2003n.html#14 Poor people's OS?
dual-use digital signature vulnerability
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Fri, 16 Jul 2004 08:31:27 -0600
To: cryptography@xxxxxxxx
Subject: dual-use digital signature vulnerability
ok, this is a long posting about what i might be able to reasonable
assume if a digital signature verifies (posting to c.p.k newsgroup):
http://www.garlic.com/~lynn/2004h.html#14
basically the relying-party has certified the environment that houses
the private key and the environment that the digital signature was
done in ... then the verification of the digital signature might be
assumed to imply one-factor or possibly two-factor authentication
(i.e. if the relying-party has certified that a private key is housed
in a secure hardware token and can never leave that hardware token,
then the verification of the digital signature might imply one-factor,
something you have authentication).
that establishes the basis for using digital signature for
authentication purposes ... being able to assume that verification of
the digital signature possibly implies something you have
authentication (or something similar).
just the verification of the digital signature, however doesn't do
anything to establish any implication about a legal signature where
the "signer" is assumed to have read and agrees to the contents of the
thing being signed (intention to sign the content of the document as
agreement, approval, and/or authorization).
lets assume for argument sake that some sort of environment can be
certified that provides a relying party some reasonable assurance that
the signer has, in fact, read and is indicating agreement, approval,
and/or authorization ... then there might possible be the issue of the
dual-use vulnerability.
the dual-use comes up when the person is signing random challenges
as purely a means of authentication w/o any requirement to read the
contents. Given such an environment, an attack might be sending some
valid text in lieu of random data for signature. Then the signer may
have a repudiation defense that he hadn't signed the document (as in
the legal sense of signing), but it must have been a dual-use attack
on his signature (he had signed it believing it to be random data as
part of an authentication protocol).
Using crypto against Phishing, Spoofing and Spamming
Refed: **, - **, - **, - **
From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Sat, 17 Jul 2004 09:25:41 -0600
To: Florian Weimer <fw@xxxxxxxx>
Subject: Re: Using crypto against Phishing, Spoofing and Spamming...
Cc: hal@xxxxxxxx, cryptography@xxxxxxxx
At 10:46 AM 7/10/2004, Florian Weimer wrote:
But is it so harmful? How much money is lost in a typical phishing
attack against a large US bank, or PayPal? (I mean direct losses due
to partially rolled back transactions, not indirect losses because of
bad press or customer feeling insecure.)
misc. recent selections
Online Phishing Scams Exploding
http://itmanagement.earthweb.com/secu/article.php/3382341
Business faces growing loss from identity theft
http://www.vnunet.com/news/1156655
Firms hit hard by identity theft
http://www.boston.com/business/technology/articles/2004/07/14/firms_hit_hard_by_identity_theft/
ID theft costing UK billions in taxes
http://news.zdnet.co.uk/0,39020330,39160532,00.htm
ATM skimmers go hi-tech down under
http://www.finextra.com/fullstory.asp?id=12184
Phishing will cost financial firms $400m in 2004
http://www.finextra.com/fullstory.asp?id=12173
Worried firms consider email boycott
http://www.vnunet.com/news/1156684
social engineering has frequently been talking somebody into giving up
some information that then can be used for impersonation in later
fraudulent transactions. A something you have token of some sort is
a lot harder to give-up than shared-secrets for use in something you
know authentication. A private key that never leaves the hardware
token can't be given up because even the owner doesn't know it. also,
conjecture is that it is a lot harder to convince general public to
mail off some physical object compared to getting them to divulge some
information.
hardware tokens don't eliminate social engineering attacks where the
victim is talked into performing some transaction on behalf of the
attacker ... but they would tend to address the whole vulnerability
landscape related to something you know shared-secret authentication
paradigms.
one of the cost issues with technology for server reputation is that
it typically applies to servers that the consumer is visiting for the
first time (or visits extremely rarely). the consumer pretty much
ignores repetitive information for sites that they visit
frequently. it has been that something like ninety percent (or better)
of internet transactions are done by the frequently visited sites. so
the cost issue is that the reputation technologies basically tend to
apply to the millions of low-volume and/or low-revenue sites (in
aggregate accounting for 10 percent or less of all transactions)
... which aren't looking to spend a lot of money on such technologies.
it is somewhat like the better business bureau use .... people will
tend to contact the better business bureau before they deal with some
vendor for the first time .... but they aren't likely to contact the
better business bureau each time they deal with a vendor that they
have extensive repeat business with. it at least some scenarios ....
an alternative to the business logo .... is a better business bureau
or gov. licensing logo on a website .... that provides click-thru to
the official site .... where the consumer can review complaints and/or
history about the business in question. i believe that this is
somewhat the ebay model ... where past transaction history reputation
of individuals can be checked.
dual-use digital signature vulnerability
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Sun, 18 Jul 2004 08:54:56 -0600
To: Amir Herzberg <herzbea@xxxxxxxx>
Subject: Re: dual-use digital signature vulnerability
Cc: Anne & Lynn Wheeler <lynn@xxxxxxxx>, cryptography@xxxxxxxx
At 01:33 AM 7/18/2004, Amir Herzberg wrote:
I don't see here any problem or attack. Indeed, there is difference
between signature in the crypto sense and legally-binding
signatures. The later are defined in one of two ways. One is by the
`digital signature` laws in different countries/states; that approach
if often problematic, since it is quite tricky to define in a general
law a binding between a person or organization and a digital
signature. The other way however is fine, imho: define the digital
signature in a (`regular`) contract between the parties. The contract
defines what the parties agree to be considered as equivalent to their
(physical) signature, with well defined interpretation and
restrictions.
...
the digital signature laws, for the most part, defined how a
certification authority went about binding the owner of a public key
(or at least the entity presenting a public key and a digital
signature that could be verified by that public key) and some other
information ... and presenting that in a certificate. However, I don't
remember seeing any of the e-sign laws a) defining a non-repudiation
environment that is mandated for signature digital signing environments
(indicating that the key owner has read, understood, and approves,
agrees, and/or authorizes the contents of the message and b) as
part of the integrity of the message, there is proof that such a
non-repudiation environment was used.
1)
the relying party being able to certify the integrity level of
something like a hardware token .... for use in something you have
authentication .... aka the relying party verifies a digital signature
and that verification may used to imply something you have
authentication (at this point there is absolutely nothing involving a
certificate). However, in order for the relying party to be able to
assume or imply what the verification of the digital signature
actually means .... and therefor how much it can trust the
verification ... it needs to know how the private key is maintained
and operated. If the act of verifying a digital signature actually
means or implies that it is something you have authentication
... then it needs to have some certification along the lines that the
private key is used and maintained in a hardware token with specific
characteristics. It has nothing at all to do with any certificate
traditionally mentioned in various kinds of e-sign laws.
2)
during the early '90s, the identity certificates tended to be
overloaded with all sorts of identity and privacy information. this
was fairly quickly realized to represent serious privacy and liability
issues. this was retrenched to things like relying-party-only
certificates that basically only had a public key and some sort of
account identifier (which could be used by the relying party to pull
up the real information .... w/o having it publicly broadcast all over
the world). However, there were also things like non-repudiation
bits defined in certificates ... that have since been severely
depreciated. During the mid-90s there were some infrastructures being
proposed that if you had some data which had an appended digital
signature and an appended certificate containing a non-repudiation bit
.... then the burden of proof (in disputes) could be shifted from the
relying party to the signing party.
This was vulnerable to possibly two exploits
a) the digital signer had believed that they had signed random data as
part of an authentication protocol ... as opposed to having signed
some document contents indicating agreement, approval, and/or
authorization (as in real live signature .... aka the dual-use
scenario) and/or
b) since the appended certificate isn't part of the signed transaction
.... the relying-party might be able to find a digital certificate
(belonging to that key-owner for the same public key) that had the
non-repudiation bit set and substitute a non-repudiation certificate
for the certificate that the key-owner had actually appended (aka the
certificate is not part of the integrity of the message covered under
the digital signature).
3)
at the NIST PKI workshop a couple months ago .... there were a number
of infrastructure presentations where various entities in the
infrastructure were
a) signing random data as part of authentication protocol (where the
entity performing the digital signature was given no opportunity to
view the contents being signed) they were using hardware token
implementation .... and they were assuming that the verification of
the digital signature implied some sort of something you have
authentication. however there was nothing in the infrastructure that
provided certification and/or proof that the private key was kept and
maintained in a hardware token .... so there was no proof as to the
level of integrity and/or level of trust that the relying party could
place in the verification of that digital signature
used in the authentication protocols)
However, there was no distinguishing and/or provable characteristics
that were provided which a relying-party could use to distinguish
between (random) contents that were signed as part of an
authentication protocol and (authorization) contents ... where the
relying-party could assume to indicate that the signer was agreeing,
approving, and/or authorization what was indicated by the contents of
the document.
Since there was no proof provided to the relying-party as to the
environment and conditions under which the signing actually occurred
.... then a dual-use attack is for non-random contents (aka some sort
of authorization document) to be injected into an authentication
protocol .... under the assumption that the entity performing the
digital signature will never look at the contents. Then such digitally
signed contents can be used in an approval, agreement, and/or
authorization scenario to imply that the entity performing the digital
signature was actually approving the contents of the document.
4)
this now verges into various of the non-repudiation definitions
and threads that have occurred in the past. in effect, for any kind of
infrastructure where the digital signature is being used to imply that
the token-owning entity (responsible for the digital) signature
agrees, approves, and/or authorizes what is in the content of the
message being signed (as opposed to some random data being signed as
part of authentication protocol and is never viewed) ... there has to
be some additional signing environment (demonstrating that the signer
has actually read, understood, and agrees with the contents) ... and
the proof of the use of such a signing environment infrastructure has
to be carried as part of the integrity of the message .... in order
for the relying party to rely on it being a real signature
signing event ... as opposed to have really originated from an
authentication protocol where the person believed that random data was
being signed (and never actually viewed the contents being
signed). Note that not only does such an non-repudiation
signing environment need to have been used .... but the proof of its
use has to be carried as part of the integrity of the message (in
order for the relying party to distinguish between random data being
digital signed and case where the person having signed after viewing
the contents, understanding the contents and approving, agreeing,
and/or authorization what was indicated by the contents). So it isn't
just that a non-repudiation environment has to be used for
signing operations (as in human signature) ...but the proof of such
non-repudiation environments have to be carried as part of the
integrity of the message .... to differentiate from a dual-use attack
where the signing is believed to be random data and the person never
views the contents.
5)
other kinds of infrastructure implementations may be to have two
completely different hardware tokens with two completely different
public/private key pairs.
the hardware token used for authentication protocols doesn't concern
itself with the contents of the data ... in fact it always appends a
disclaimer to all random data (that it signs) stating that the digital
signature cannot be used to imply any agreement, approval,
authorization and/or any obligation on the part of the
token-owning entity.
the hardware token used for authorization, agreement, and/or approval
signing events will never perform a digital signature operation unless
it first senses that the token owner has read, understood and
approved of the contents.
all protocols indicate as part of the hardware token interaction, which
type of digital signature will be performed ... and the owner of the
hardware tokens is then instructed appropriately when hardware token
swapping needs to occur.
=========
random past posts about non-repudiation:
http://www.garlic.com/~lynn/aadsm10.htm#cfppki15 CFP: PKI research workshop
http://www.garlic.com/~lynn/aadsm10.htm#cfppki18 CFP: PKI research workshop
http://www.garlic.com/~lynn/aadsm10.htm#paiin PAIIN security glossary & taxonomy
http://www.garlic.com/~lynn/aadsm11.htm#5 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#6 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#7 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#8 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#9 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#11 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#12 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#13 Words, Books, and Key Usage
http://www.garlic.com/~lynn/aadsm11.htm#14 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm11.htm#15 Meaning of Non-repudiation
http://www.garlic.com/~lynn/aadsm12.htm#5 NEWS: 3D-Secure and Passport
http://www.garlic.com/~lynn/aadsm12.htm#12 TOC for world bank e-security paper
http://www.garlic.com/~lynn/aadsm12.htm#30 Employee Certificates - Security Issues
http://www.garlic.com/~lynn/aadsm12.htm#37 Legal entities who sign
http://www.garlic.com/~lynn/aadsm12.htm#38 Legal entities who sign
http://www.garlic.com/~lynn/aadsm12.htm#59 e-Government uses "Authority-stamp-signatures"
http://www.garlic.com/~lynn/aadsm14.htm#39 An attack on paypal
http://www.garlic.com/~lynn/aadsm14.htm#47 UK: PKI "not working"
http://www.garlic.com/~lynn/aadsm14.htm#48 basic question: semantics of "map", "tie", etc in PKI
http://www.garlic.com/~lynn/aadsm15.htm#32 VS: On-line signature standards
http://www.garlic.com/~lynn/aadsm15.htm#33 VS: On-line signature standards
http://www.garlic.com/~lynn/aadsm15.htm#34 VS: On-line signature standards (slight addenda)
http://www.garlic.com/~lynn/aadsm15.htm#35 VS: On-line signature standards
http://www.garlic.com/~lynn/aadsm15.htm#36 VS: On-line signature standards
http://www.garlic.com/~lynn/aadsm16.htm#11 Difference between TCPA-Hardware and a smart card (was: example: secure computing kernel needed)
http://www.garlic.com/~lynn/aadsm16.htm#13 The PAIN mnemonic
http://www.garlic.com/~lynn/aadsm16.htm#14 Non-repudiation (was RE: The PAIN mnemonic)
http://www.garlic.com/~lynn/aadsm16.htm#17 Non-repudiation (was RE: The PAIN mnemonic)
http://www.garlic.com/~lynn/aadsm16.htm#18 Non-repudiation (was RE: The PAIN mnemonic)
http://www.garlic.com/~lynn/aadsm16.htm#23 Non-repudiation (was RE: The PAIN mnemonic)
http://www.garlic.com/~lynn/aadsm17.htm#3 Non-repudiation (was RE: The PAIN mnemonic)
http://www.garlic.com/~lynn/aadsm17.htm#5 Non-repudiation (was RE: The PAIN mnemonic)
http://www.garlic.com/~lynn/aadsm17.htm#55 Using crypto against Phishing, Spoofing and Spamming
http://www.garlic.com/~lynn/2000.html#57 RealNames hacked. Firewall issues.
http://www.garlic.com/~lynn/2001c.html#30 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#34 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#39 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#40 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#41 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#42 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#43 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#44 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#45 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#46 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#47 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#50 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#51 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#52 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#54 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#56 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#57 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#58 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#59 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#60 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#72 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001c.html#73 PKI and Non-repudiation practicalities
http://www.garlic.com/~lynn/2001g.html#11 FREE X.509 Certificates
http://www.garlic.com/~lynn/2001g.html#38 distributed authentication
http://www.garlic.com/~lynn/2002f.html#35 Security and e-commerce
http://www.garlic.com/~lynn/2002g.html#37 Security Issues of using Internet Banking
http://www.garlic.com/~lynn/2002g.html#69 Digital signature
http://www.garlic.com/~lynn/2002h.html#68 Are you really who you say you are?
http://www.garlic.com/~lynn/2002i.html#67 Does Diffie-Hellman schema belong to Public Key schema family?
http://www.garlic.com/~lynn/2002i.html#77 Does Diffie-Hellman schema belong to Public Key schema family?
http://www.garlic.com/~lynn/2002j.html#24 Definition of Non-Repudiation ?
http://www.garlic.com/~lynn/2002j.html#40 Beginner question on Security
http://www.garlic.com/~lynn/2002m.html#38 Convenient and secure eCommerce using POWF
http://www.garlic.com/~lynn/2002n.html#16 Help! Good protocol for national ID card?
http://www.garlic.com/~lynn/2002n.html#19 Help! Good protocol for national ID card?
http://www.garlic.com/~lynn/2003.html#19 Message (authentication/integrity); was: Re: CRC-32 collision
http://www.garlic.com/~lynn/2003.html#29 Message (authentication/integrity); was: Re: CRC-32 collision
http://www.garlic.com/~lynn/2003f.html#37 unix
http://www.garlic.com/~lynn/2003h.html#29 application of unique signature
http://www.garlic.com/~lynn/2003h.html#38 entity authentication with non-repudiation
http://www.garlic.com/~lynn/2003i.html#35 electronic-ID and key-generation
http://www.garlic.com/~lynn/2003i.html#36 electronic-ID and key-generation
http://www.garlic.com/~lynn/2003j.html#47 The Tao Of Backup: End of postings
http://www.garlic.com/~lynn/2003k.html#6 Security models
http://www.garlic.com/~lynn/2003m.html#38 Questioning risks of using the same key for authentication and encryption
http://www.garlic.com/~lynn/2003o.html#22 securID weakness
http://www.garlic.com/~lynn/2003o.html#29 Biometric cards will not stop identity fraud
http://www.garlic.com/~lynn/2003p.html#4 Does OTP need authentication?
http://www.garlic.com/~lynn/2003p.html#11 Order of Encryption and Authentication
http://www.garlic.com/~lynn/2003p.html#17 Does OTP need authentication?
http://www.garlic.com/~lynn/2004e.html#20 Soft signatures
Using crypto against Phishing, Spoofing and Spamming
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From: Anne & Lynn Wheeler <lynn@xxxxxxxx>
Date: Sun, 18 Jul 2004 09:51:46 -0600
To: EKR <ekr@rtfm.com>
Subject: Re: Using crypto against Phishing, Spoofing and Spamming...
Cc: Ian Grigg <iang@xxxxxxxx>, Florian Weimer <fw@xxxxxxxx>,
cryptography@xxxxxxxx
At 05:55 PM 7/17/2004, Eric Rescorla wrote:
Now, my threat model mostly includes (1), does not really include
(3), and I'm careful not to do things that leave me susceptible
to (2), so SSL does in fact protect against the attacks in my
threat model. I know a number of other people with similar threat
models. Accordingly, I think the claim that "secure browsing
is not secure" rather overstates the case.
there sort of two parts of SSL .... I believe the original
justification was based on perceived integrity issues with the domain
name infrastructure and various kinds of hijacking attacks. the client
got back a certificate, verified the integrity of the certificate
(from a table of certificate authority public keys), verified that it
appeared to originate from the certificate owner and then compared the
certificate domain name string with the domain name used in the
URL. once that was done, there was key-exchange to protect the
contents of the transmission.
the catch-22 was that the domain name infrastructure is also the
authoritative agency as to the owner of the domain name. the SSL
domain name certification authorities have this horrendously, error
prone and expensive problem of getting sufficient identification
information from the certificate applicant and attempting to match it
with the identification information carried by the domain name
infrastructure as to the owner of the domain name.
so the first issue is that the integrity of the domain name
infrastructure could be attacked with a domain name hijack ... then
the attacker applies for a certificate .... and the identification
provided the certification authority and the identification on file
with the domain name infrastructure compare ... and the attacker gets
a valid certificate.
so the certification authorities came up with a proposal to have
domain name registers .... also supply a public key at the time of
registration. then future communication with the domain name owner is
digital signed ... which the domain name infrastructure can verify
with the public key on file. this is a countermeasure against domain
name hijacking (improving the integrity of the domain name
infrastructure and rising the trust that certification authorities can
place in the authoritative agency). the other issue is that the
certification authorities can use the public key on file with the
domain name infrastructure to turn an expensive, and error-prone
identification process into a much simpler and KISS authentication
process .... aka domain name certificate applicants digitally sign
their requests ... which are then verified with the public key on file
at the domain name infrastructure.
the two issues then are that with increased domain name infrastructure
trust ... 1) it should reduce the demand for domain name SSL
certificates (motivated by integrity concerns about the domain name
infrastructure) and 2) it could eliminate the need for domain name SSL
certificates .... since all clients could possibly also use the public
keys on file with the domain name infrastructure (in lieu of needing
to get public keys from certificates).
So now to the key-exchange issue protecting credit-card numbers from
evesdropping and harvesting. The issue is that the crooks tend to go
after the best fraud ROI (return on investment). The claim is that it
is so much more profitable to harvest the merchant transaction file
.... that until that barn door is closed .... the crooks have little
incentive to go after credit card numbers by evesdropping packets in
flight. There have been some assertions that there has been no known
cases of picking up account numbers from packet evesdropping .... even
where SSL or any other encryption is being used to protect data
in-flight. Part of the issue is that evesdropping packets takes a lot
more work ... and provides much less return than going after the
merchant transaction file. Other scenarios have also been end-point
attacks ... where password files are harvested and/or viruses are
installed at end-points to harvest information .... as opposed to
doing anything with data in-flight.
So, it could be claimed that there is some question about what is
cause and what is effect i.e. are the end-point attacks because
everything is encrypted .... or are the end-point attacks occurring
because they are so much more profitable and easier. Given that there
are significant amounts of non-encrypted traffic ... then the claim
could be made that the crooks are getting so much more from end-point
attacks ... and until that is addressed ... that attacks on data in
flight is somewhat academic (since there is so little evidence about
fraud happening from data in flight attacks). The other argument has
traditional been that 90 percent of fraud has been insiders, typically
also associated with various kinds of end-point attacks (rather than
any kind of outsider attack on data in flight). There was some recent
study that at least 77 percent of the identity theft has involved
insiders. This would also indicate that the end-points are the primary
points of attack .... and that data-in-flight attacks are of primarily
of academic interests ... not particularly contributing to fraud, even
when no encryption or protection is involved.
One might even assert that the attention paid to data-in-flight
attacks is actually counterproductive ... distracting attention from
the much more serious and significant end-point attack threats
.... which has always been the major problem.