December 2003 - cypherpunks-legacy

Re: Credit card numbers
by Jerry Whiting 17 Dec '03

17 Dec '03

Credit card check sums are based on the Luhn code. Double the odd digits (1, 3, 5, etc.). Use the sum of any 2-digit results. Add all these numbers together to end up with one single digit. Add this single digit to the sums of all the even digits. The Luhn check digit is the mod 10 of that final subtotal. For example 641205002340106 yields 4. jwhiting

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Re: Telephone card tech. howto needed
by Mutant 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Kristian Sagi wrote: [..] > Only 6 are connected ... Has anyone ideas, how this card works ... i > something like telephone card hardware tutorials or something ... I [..] What kind of telephone card? Probably a smart card with PK crypto which isn't so easy to defeat. In terms of technical details, check 2600 magazine (but avoid alt.2600, since there's more noise there than this group has) or do a web search. You might want to check other magazines like Hac Tic (no longer printed?) - --- [This message has been signed by an auto-signing service. A valid signature means only that it has been received at the address corresponding to the signature and forwarded.] -----BEGIN PGP SIGNATURE----- Version: 2.6.2 Comment: Gratis auto-signing service iQBFAwUBMSqqvSoZzwIn1bdtAQHIMQF+N7aisKNZZ+wM7sSUSRxfo7cZ2DC1maxR 8i3tFjE8yPc6CPbuQf4j5vwcPBa64D9N =IPIj -----END PGP SIGNATURE-----

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should we use same nym on multiple servers?
by nobody＠REPLAY.COM 17 Dec '03

17 Dec '03

With the additional nym servers coming on the scene comes the question of whether or not to "claim" our alpha.c2 nym on the other ones, too. E.g., if we are foobar(a)alpha.c2.org, should we also become foobar(a)nym.gondolin.org and foobar(a)nym.alias.net, too? That would let us have a very stable nym, and prevent confusion over who's "who" if someone else were to have the same id with another nym server. But, it makes it harder to keep our real ID secret. (E.g., an oversimplified scenario would be if an attacker sends a message to all three nyms, then watches three PGP conventionally encrypted messages arrive in our mailbox.) A "safer" way would be to have the other two nyms have a fake address, but then we couldn't receive mail with it. A trickier way would be to have the reply block point to alt.anonymous, but then we'd have to constantly be watching for a message "to" us. Another angle, though, is that the nym servers may be unstable, and multiple nyms would allow us to post, if out "favorite" is down. Anyways, I'm a beginner, and think that the most useful use of remailers is to ask dumb questions. :-)

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Patient medical files on Net
by Martin Diehl 17 Dec '03

17 Dec '03

WSJ - 2/20/96, page B1 "Click! Doctor to Post Patient Files on Net" by G. Bruce Knecht "An audacious experiment ... [snip] "Deep in the heart of Appalachian coal country, a doctor is about to put his patients' records on the World Wide Web. The Doctor, Bruce Merkin, works at a community health clinic in Wayne, W. Va." [snip] "Dr. Merkin and Vasudevan Jagan-nathaniel, a West Virginia University professor who is responsible for developing the software for the system, say they have yet to decide how secure the system should be. At one extreme, they could encrypt the information, offering the highest possible degree of protection. But encryption is expensive and time consuming and thus could hinder the goals of cutting costs and rapidly transmitting information." [snip] Cypherpunks: The WSJ report seems to indicate that the system is to be deployed without any encryption safeguards. After talking by phone to Lee Oxley (oxley(a)vhs.wvu.edu) at Valley Health in Wayne, WV, I got clarifications of what was in the WSJ story. The present pilot system is an intranet system with dedicated frame relay links and does use encryption. Eventually they may deploy a system that would be internet based. They are considering how much protection to put into the system. The reference in the article about encryption costs was intended to be about CPU cycles not dollars. Vasudevan Jagan-nathaniel's email address is juggy(a)cerc.wvu.edu Some obvious proposals would be to use something like SSL to do server to workstation encryption. I don't know what issues may exist such as the effort to install SSL, key management, and processing delays due to session keys and traffic encryption. In addition, how could an on-call doctor access patient records through an ISP and maintain patient privacy. An obvious issue (which I know have been discussed on this list) has to do with the trade-off between key size and privacy. Any other thoughts? Martin G. Diehl

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breakable session keys in Kerberos v4
by asantos＠retesa.es 17 Dec '03

17 Dec '03

Se han encontrado huecos en Kerberos v4. Aqui teneis la informacion: >Return-Path: <owner-cypherpunks(a)toad.com> >Received: from control (controli.retesa.es) by sun2.retesa.es (5.x/SMI-SVR4) > id AA01592; Tue, 20 Feb 1996 09:59:01 GMT >Received: by control (SMI-8.6/SMI-SVR4) > id DAA19612; Tue, 20 Feb 1996 03:02:47 -0800 >Received: from relay3.uu.net(192.48.96.8) by control via smap (V1.3) > id sma019610; Tue Feb 20 03:02:35 1996 >Received: from toad.com by relay3.UU.NET with SMTP > id QQadse08697; Tue, 20 Feb 1996 04:01:50 -0500 (EST) >Received: by toad.com id AA24982; Tue, 20 Feb 96 00:28:15 PST >Received: from sfi.santafe.edu by toad.com id AA24976; Tue, 20 Feb 96 00:28:11 PST >Received: from nelson.santafe.edu by sfi.santafe.edu (4.1/SMI-4.1) > id AA02389; Tue, 20 Feb 96 01:24:08 MST >Received: (from nelson@localhost) by nelson.santafe.edu (8.7.1/8.7.1) id BAA21074; Tue, 20 Feb 1996 01:28:01 -0700 >Date: Tue, 20 Feb 1996 01:28:01 -0700 >Message-Id: <199602200828.BAA21074(a)nelson.santafe.edu> >From: Nelson Minar <nelson(a)santafe.edu> >To: cypherpunks(a)toad.com >Subject: breakable session keys in Kerberos v4 >Sender: owner-cypherpunks(a)toad.com >Precedence: bulk >Content-Type: text >Status: O > >I'm a bit suprised this hasn't turned up yet on Cypherpunks. A couple >of forwarded messages: first, an announcement made Fri Feb 16 by Gene >Spafford at COAST about an exploitable flaw they've found in Kerberos, >and then a comment on the www-security list that it is due to a bad >random number generator. Same old story! > >The message (lifted from the COAST web site) >-----BEGIN PGP SIGNED MESSAGE----- > >Personnel at the COAST Laboratory (Computer Operations, Audit, and >Security Technology) at Purdue University have discovered a >vulnerability in current versions of the Kerberos security system. >Graduate students Steve Lodin and Bryn Dole, working with Professor >Eugene Spafford, have discovered a method whereby someone without >privileged access to most implementations of a Kerberos 4 server can >nonetheless break secret session keys issued to users. This means that >it is possible to gain unauthorized access to distributed services >available to a user without knowing that user's password. This method >has been demonstrated to work in under 1 minute, on average, using a >typical workstation, and sometimes as quickly as 1/5 second. > >The Kerberos system was developed at MIT in the mid-1980s, and has >been widely adopted for security in distributed systems worldwide. >Kerberos is most often used on UNIX platforms by various vendors, and >is often enhanced, sold and supported by 3rd-party vendors for use in >academic, government, and commercial environments. > >The same researchers at COAST have also found a small, theoretical >weakness in Kerberos version 5 that would allow similar access, given >some additional information and considerable preliminary computation. >Kerberos version 5 does not exhibit the same weakness as described >above for Kerberos version 4. > >The researchers at COAST had intended to release the specific details >of the problem to affected vendors and incident response teams during >the week of February 19, prior to making a public announcement of >their findings. However, as rumors have begun to circulate and >several representatives of the news media have apparently received >indication of the problem, we are releasing this preliminary >announcement at this time. > >Government and industry sponsors of the COAST Laboratory were made >aware of the preliminary details of these findings in January (full >sponsors receive early notification of significant discoveries as a >result of COAST research). Other affiliates of COAST as well as the >world-wide network of FIRST computer incident response teams were made >aware of the general nature of the findings during the week of >February 5. The original plan at COAST was to release specific >details only to FIRST (Forum of Incident Response and Security Teams) >teams and to MIT prior to announcement by affected vendors of a fix >for these weaknesses. The flaw in Kerberos version 4 is significant >enough that disclosure of its details prior to a fix would allow >someone with moderate programming skills to exploit it; there is >currently no reason to believe that others know the details of the >flaw and are exploiting it, so there is no immediate danger to the >public that would warrant release of the details at this time. > >COAST personnel have been informed that MIT has already developed a >fix for the flaw in version 4 Kerberos and is preparing it for >release. Additionally, COAST researchers are cooperating with MIT >personnel to identify what (if any) fixes are necessary for version 5 >Kerberos. Users of either version of Kerberos should contact their >vendors for details of any fixes that may be made available; vendors >of products incorporating Kerberos should contact MIT directly for >details of the problems and fixes. > >COAST is a research group of faculty and students dedicated to >research into information security and computer crime investigation, >and education in computer and network security. It is the largest >such university-based group in the United States. > >Information on COAST may be found on the WWW at > http://www.cs.purdue.edu/coast >Information on FIRST teams may be found on the WWW at > http://www.first.org >Information on MIT's Kerberos may be found on the WWW at > ftp://athena-dist.mit.edu/pub/kerberos/doc/KERBEROS.FAQ > >-----BEGIN PGP SIGNATURE----- >Version: 2.6.2 >Comment: Key @ ftp://ftp.cs.purdue.edu/pub/spaf/pers/pgpkey.asc > >iQCVAwUBMSZ42cpvK4P8DALVAQHg8QP/TRmqwP7vG32aaBjvbMof2iuVQ2bcWrg9 >p55KN5wBfrBzxq5/NE+6lodkqq2w1ib8q/47uYT1S8iR+z2tnbvL64dxrtDEh4iY >iEWjfpTMtQxLmZ1gA3Sxxn4A+6KwlXq5z4Lp2BROUXyeSR7HPAEeEQucRNWkzz8o >IOMHuBAcBKo= >=yWxe >-----END PGP SIGNATURE----- > >(a comment I found in reply) > >------- Start of forwarded message ------- >From: jis(a)mit.edu (Jeffrey I. Schiller) >Subject: Re: Kerberos Vulnerability >Newsgroups: hks.lists.www-security >Date: 19 Feb 1996 21:42:08 -0500 >Organization: HKS, Inc. >Path: hks.net!news-mail-gateway!owner-www-security >Lines: 8 >Sender: root(a)hks.net >Message-ID: <ad4e9fc40602100421be(a)[18.162.1.1]> >NNTP-Posting-Host: bb.hks.net > >There will be a fix distributed by MIT later this week. The problem is that >the random number generator in V4 is worse then we thought! The fix is to >retrofit the V5 generator (which is decent) into the V4 KDC. Note: Only the >KDC needs to be updated, clients and servers are unaffected. > > -Jeff > > >------- End of forwarded message ------- > > Agustín Santos Méndez, RETESA, S.A. C/Orense 4, Planta 10. 28020 MADRID SPAIN. Ph: +34.1.342.67.91 Fax +34.1.597.28.77 E-mail: asantos(a)retesa.es

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Re: Internet Privacy Guaranteed ad (POTP Jr.)
by Mutant 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- IPG Sales wrote: [Notice "Sales" wrote this...] > We are not currently revealing all the details of our system because of > patents in process, and other relat6ed matters. We are offering the Do you know what "patent pending" means? > software. You should be able to readily decompile it and determine the > algorithms used andf how they are used to generate random number sequences If you're so concerned about secrecy and patents, why encourage anyone to reverse engineer it? If it's as secure as you say (and it's not) and yet unpatented, then you sure as hell don't want anyone reverse engineering it... you don't even want to publish the compiled binary either (if that were true). [..] > If you are aware of encrtypting technology, you recognize that hardware > prime number cycle wheels for the basis of some of the most secured > hardware systems employed for encryption. We simply expand that You mean like Enigma machines? (chuckle) > Thus we can eliminate the need to have the length of the OTP to be equal > to the length of the file - if you do not belive that it works, try it > and see - it takes inly a few hours to set such a trial up. We generated OTP = One Time Pad ^^^ Used once. Not repeated. Equals the size of the file. Completely erased from the cosmos after decryption and never seen again. Anything else just isn't a one time pad. > over 790 gigabytes of charcaters, on multiple backups, and tested. Our > standard deviations, chi squares, Delta ICs for bits, characters, sets, > and the entire set were random. The sets are random, and you can take > that to the bank. Gee. It sure looks random. Must be secure. [Sarcarm mode off] > Someone, will decompile it and discover that it is truly random, at least > from the practical usage basis. But we need that time to file patents, > cvopyrights and the like. Truly random? If it's based on an algorithm and not an unpredictable source of external randomness, it just ain't random. If it's fed the same seed, will it produce the same output? If so, 'taint random. Don't call it that. Just don't. > The IPG system solves the key management problem and produces a truly Oh really? And how does it do that? ... [..] > "Unless we know, we do not experience by talking," Plato Interesting that you quote Plato, who believed in such fairy tales as essential orbs of "truth", "beauty", etc. floating around in some neuminal hyperspace. Faith was rather important, and the western religions were really damn peachy about it. Oh, I get it... OTP stands for Onto-Theological Platonism. Philisophical snake oil... - --- [This message has been signed by an auto-signing service. A valid signature means only that it has been received at the address corresponding to the signature and forwarded.] -----BEGIN PGP SIGNATURE----- Version: 2.6.2 Comment: Gratis auto-signing service iQBFAwUBMSqxhCoZzwIn1bdtAQFrnwGAxffXmBmuZchYHTFapCNqc5xxiEqDy7BD RL9cJeuP/2CHnVUgvfRX5uHfabPZz+Z7 =akNJ -----END PGP SIGNATURE-----

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Symantec Caf�
by asantos＠retesa.es 17 Dec '03

17 Dec '03

La empresa Symantec ha sacado al mercado un entorno de programacion JAVA para WindowsŽ95/NT. Quien se apunta a evaluarlo? El URL es :"http://www.symantec.com/lit/dev/javaindex.html" o bien :"http://www.symantec.com/lit/dev/java.html" Agustín Santos Méndez, RETESA, S.A. C/Orense 4, Planta 10. 28020 MADRID SPAIN. Ph: +34.1.342.67.91 Fax +34.1.597.28.77 E-mail: asantos(a)retesa.es

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Re: Secure Split
by loki＠obscura.com 17 Dec '03

17 Dec '03

I wrote a program which does secret sharing calles SecShare. It is on my home page. As my first venture into crypto programming it is a major kludge, but it does the job. -Lance ---------------------------------------------------------- Lance Cottrell loki(a)obscura.com PGP 2.6 key available by finger or server. Mixmaster, the next generation remailer, is now available! http://obscura.com/~loki/Welcome.html or FTP to obscura.com "Love is a snowmobile racing across the tundra. Suddenly it flips over, pinning you underneath. At night the ice weasels come." --Nietzsche ----------------------------------------------------------

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Re: Internet Privacy Guaranteed ad (POTP Jr.)
by Peter Trei 17 Dec '03

17 Dec '03

ipgsales(a)cyberstation.net writes [...] - I do not now what KDC's are... [...] > Incidentally crypto wheel systems are still employed in 1996 at some of > the highest levels of usage - some called then rotors at one time - they > are still used because the produce non repeatable sequeces It's sort of amazing that a person can show themselves so foolish and ignorant in less than four full lines of text. No person or organization who has studied crypto beyond the Captain Midnight Decoder Ring level can take these people or their product seriously. Peter Trei ptrei(a)acm.org

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Re: Web Browsers and Anonymous Mail (Was: NSA net trolling)
by frantz＠netcom.com 17 Dec '03

17 Dec '03

>(0) I'm not aware of any class library objects or methods in stand-alone Java >for calling the local mail transport agent. Is there any class library >support in Java+{Navigator, HotJava, Mosaic, NetCruiser, the AOL web tool, >etc.} for applet calls to the local mail agent that's configured in the >browser ? A look at the documentation does not show one. You may have to implement the whole MTA protocol yourself :-(. It does occur to me that such a library would only be possible in a browser that knows (via configuration) how to find MTAs. Good luck - Bill ------------------------------------------------------------------------ Bill Frantz | The CDA means | Periwinkle -- Computer Consulting (408)356-8506 | lost jobs and | 16345 Englewood Ave. frantz(a)netcom.com | dead teenagers | Los Gatos, CA 95032, USA

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