1 rsa-md5-collision README -- Information about rsa-md5-collision self tests.
2 Copyright (C) 2006-2012 Free Software Foundation, Inc.
3 See the end for copying conditions.
5 This directory contains colliding X.509 certificates for different
8 http://www.win.tue.nl/hashclash/TargetCollidingCertificates/
10 The certificates are used by a simple self-test script,
11 rsa-md5-collision, that check to make sure that GnuTLS reject both
14 Below is the e-mail exchanges with the authors where they agree to
15 release the certificates under a permissive license, that allow the
16 files to be included here.
18 X-Hashcash: 1:22:061024:m.m.j.stevens@student.tue.nl::NIoLZwQj6TTZ4YZK:BUuA
19 X-Hashcash: 1:22:061024:arjen.lenstra@epfl.ch::NgTq8sJW1QBlX/rv:g9Z
20 From: Simon Josefsson <jas@extundo.com>
21 To: "Weger\, B.M.M. de" <b.m.m.d.weger@TUE.nl>, m.m.j.stevens@student.tue.nl, arjen.lenstra@epfl.ch
22 Subject: Re: target collisions and colliding certificates with different identities
23 References: <DFA3206A564B80499B87B89B49BCD3135DC17A@EXCHANGE3.campus.tue.nl>
24 OpenPGP: id=B565716F; url=http://josefsson.org/key.txt
25 X-Draft-From: ("gmane.ietf.irtf.cfrg" 784)
26 X-Hashcash: 1:22:061024:b.m.m.d.weger@tue.nl::aYYmnRc08nJKaUMk:6ddD
27 Date: Tue, 24 Oct 2006 08:28:07 +0200
28 In-Reply-To: <DFA3206A564B80499B87B89B49BCD3135DC17A@EXCHANGE3.campus.tue.nl>
29 (B. M. M. de Weger's message of "Mon\, 23 Oct 2006 23\:58\:21 +0200")
30 Message-ID: <87ods2grd4.fsf@latte.josefsson.org>
31 User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/22.0.50 (gnu/linux)
33 Content-Type: text/plain; charset=us-ascii
35 Xref: localhost.localdomain rsa-md5:1
39 I'd like to include your certificates in GnuTLS, a TLS implementation
40 that supports X.509, as self-tests of the certificate verification
41 logic. Is this OK with you?
43 Btw, Gnutls rejected the certificates, we already disable MD5 for
44 verification purposes. :)
46 For our legal department, I'd like a clarification of the license on
47 the data, would you agree to release the certificates under the
50 Copyright (c) 1996 Marc Stevens, Arjen K. Lenstra, Benne de Weger
52 Copying and distribution of this file, with or without modification,
53 are permitted in any medium without royalty provided the copyright
54 notice and this notice are preserved.
56 Also, if any other authors contributed, they would have to agree to
57 this license as well. Are there other authors?
59 Best regards, and thanks in advance,
62 "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl> writes:
67 > - an example of a target collision for MD5; this means:
68 > for two chosen messages m1 and m2 we have constructed
69 > appendages b1 and b2 to make the messages collide
70 > under MD5, i.e. MD5(m1||b1) = MD5(m2||b2);
71 > said differently: we can cause an MD5 collision for
72 > any pair of distinct IHVs;
73 > - an example of a pair of valid, unsuspicious X.509
74 > certificates with distinct Distinguished Name fields,
75 > but identical CA signatures; this example makes use
76 > of the target collision.
78 > See http://www.win.tue.nl/hashclash/TargetCollidingCertificates/,
79 > where the certificates and a more detailed announcement
85 Return-Path: <arjen.lenstra@epfl.ch>
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103 Content-Type: text/plain;
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106 Subject: RE: target collisions and colliding certificates with different identities
107 Date: Tue, 24 Oct 2006 08:31:42 +0200
108 Message-ID: <D449110BB7036C4297225E473599E77067DD0A@rex1.intranet.epfl.ch>
109 In-Reply-To: <87ods2grd4.fsf@latte.josefsson.org>
111 X-MS-TNEF-Correlator:
112 Thread-Topic: target collisions and colliding certificates with different identities
113 Thread-Index: Acb3NZO8kzaCp7NPSV29z2Ydtt/p5gAAEyEg
114 From: "Arjen Lenstra" <arjen.lenstra@epfl.ch>
115 To: "Simon Josefsson" <jas@extundo.com>,
116 "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl>,
117 <m.m.j.stevens@student.tue.nl>
118 X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00 autolearn=ham
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124 Xref: localhost.localdomain rsa-md5:2
128 I can't speak for my coauthors, but it's all fine with me, though I find =
129 the year in your proposed copyright statement a bit odd (I would have =
130 expected 2006). There are no more authros involved.
132 best regards, Arjen Lenstra
135 Arjen K. Lenstra a k l @ e p f l . c h
137 INJ 330 (B=E2timent INJ)
139 CH-1015 Lausanne, Switzerland
140 T=E9l: + 41 21 693 8101
141 Fax: + 41 21 693 7550
145 -----Original Message-----
146 From: Simon Josefsson [mailto:jas@extundo.com]=20
147 Sent: Tuesday, October 24, 2006 8:28 AM
148 To: Weger, B.M.M. de; m.m.j.stevens@student.tue.nl; Arjen Lenstra
149 Subject: Re: target collisions and colliding certificates with different =
154 I'd like to include your certificates in GnuTLS, a TLS implementation
155 that supports X.509, as self-tests of the certificate verification
156 logic. Is this OK with you?
158 Btw, Gnutls rejected the certificates, we already disable MD5 for
159 verification purposes. :)
161 For our legal department, I'd like a clarification of the license on
162 the data, would you agree to release the certificates under the
165 Copyright (c) 1996 Marc Stevens, Arjen K. Lenstra, Benne de Weger
167 Copying and distribution of this file, with or without =
169 are permitted in any medium without royalty provided the copyright
170 notice and this notice are preserved.
172 Also, if any other authors contributed, they would have to agree to
173 this license as well. Are there other authors?
175 Best regards, and thanks in advance,
178 "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl> writes:
183 > - an example of a target collision for MD5; this means:=20
184 > for two chosen messages m1 and m2 we have constructed=20
185 > appendages b1 and b2 to make the messages collide=20
186 > under MD5, i.e. MD5(m1||b1) =3D MD5(m2||b2);
187 > said differently: we can cause an MD5 collision for=20
188 > any pair of distinct IHVs;
189 > - an example of a pair of valid, unsuspicious X.509=20
190 > certificates with distinct Distinguished Name fields,=20
191 > but identical CA signatures; this example makes use=20
192 > of the target collision.
194 > See http://www.win.tue.nl/hashclash/TargetCollidingCertificates/,
195 > where the certificates and a more detailed announcement=20
201 From: Simon Josefsson <jas@extundo.com>
202 To: "Arjen Lenstra" <arjen.lenstra@epfl.ch>
203 Cc: "Weger\, B.M.M. de" <b.m.m.d.weger@TUE.nl>, <m.m.j.stevens@student.tue.nl>
204 Subject: Re: target collisions and colliding certificates with different identities
205 References: <D449110BB7036C4297225E473599E77067DD0A@rex1.intranet.epfl.ch>
206 OpenPGP: id=B565716F; url=http://josefsson.org/key.txt
207 X-Draft-From: ("nnimap+yxa:INBOX.private.2006.10" 623)
208 X-Hashcash: 1:22:061024:b.m.m.d.weger@tue.nl::pMR7JuXUTTt/Zjut:0aGD
209 X-Hashcash: 1:22:061024:arjen.lenstra@epfl.ch::juw1iXMSKV62mZGj:CBbu
210 X-Hashcash: 1:22:061024:m.m.j.stevens@student.tue.nl::SJdQwxRXP39Dw2C4:n6ia
211 Date: Tue, 24 Oct 2006 08:43:59 +0200
212 In-Reply-To: <D449110BB7036C4297225E473599E77067DD0A@rex1.intranet.epfl.ch>
213 (Arjen Lenstra's message of "Tue\, 24 Oct 2006 08\:31\:42 +0200")
214 Message-ID: <87d58igqmo.fsf@latte.josefsson.org>
215 User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/22.0.50 (gnu/linux)
217 Content-Type: text/plain; charset=iso-8859-1
218 Content-Transfer-Encoding: 8bit
220 Xref: localhost.localdomain rsa-md5:3
222 "Arjen Lenstra" <arjen.lenstra@epfl.ch> writes:
226 > I can't speak for my coauthors, but it's all fine with me, though I
227 > find the year in your proposed copyright statement a bit odd (I
228 > would have expected 2006). There are no more authros involved.
230 Thanks. Duh, I meant 2006, of course. I'd appreciate if Marc and
235 > best regards, Arjen Lenstra
238 > Arjen K. Lenstra a k l @ e p f l . c h
240 > INJ 330 (Bâtiment INJ)
242 > CH-1015 Lausanne, Switzerland
243 > Tél: + 41 21 693 8101
244 > Fax: + 41 21 693 7550
248 > -----Original Message-----
249 > From: Simon Josefsson [mailto:jas@extundo.com]
250 > Sent: Tuesday, October 24, 2006 8:28 AM
251 > To: Weger, B.M.M. de; m.m.j.stevens@student.tue.nl; Arjen Lenstra
252 > Subject: Re: target collisions and colliding certificates with different identities
254 > Great work, thanks!
256 > I'd like to include your certificates in GnuTLS, a TLS implementation
257 > that supports X.509, as self-tests of the certificate verification
258 > logic. Is this OK with you?
260 > Btw, Gnutls rejected the certificates, we already disable MD5 for
261 > verification purposes. :)
263 > For our legal department, I'd like a clarification of the license on
264 > the data, would you agree to release the certificates under the
267 > Copyright (c) 1996 Marc Stevens, Arjen K. Lenstra, Benne de Weger
269 > Copying and distribution of this file, with or without modification,
270 > are permitted in any medium without royalty provided the copyright
271 > notice and this notice are preserved.
273 > Also, if any other authors contributed, they would have to agree to
274 > this license as well. Are there other authors?
276 > Best regards, and thanks in advance,
279 > "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl> writes:
284 >> - an example of a target collision for MD5; this means:
285 >> for two chosen messages m1 and m2 we have constructed
286 >> appendages b1 and b2 to make the messages collide
287 >> under MD5, i.e. MD5(m1||b1) = MD5(m2||b2);
288 >> said differently: we can cause an MD5 collision for
289 >> any pair of distinct IHVs;
290 >> - an example of a pair of valid, unsuspicious X.509
291 >> certificates with distinct Distinguished Name fields,
292 >> but identical CA signatures; this example makes use
293 >> of the target collision.
295 >> See http://www.win.tue.nl/hashclash/TargetCollidingCertificates/,
296 >> where the certificates and a more detailed announcement
302 Return-Path: <m.m.j.stevens@student.tue.nl>
303 Received: from yxa.extundo.com ([unix socket])
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327 Message-ID: <03cf01c6f73c$a8923390$8702a8c0@s478591>
328 From: "Marc Stevens" <m.m.j.stevens@student.tue.nl>
329 To: "Simon Josefsson" <jas@extundo.com>,
330 "Arjen Lenstra" <arjen.lenstra@epfl.ch>
331 Cc: "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl>
332 References: <D449110BB7036C4297225E473599E77067DD0A@rex1.intranet.epfl.ch> <87d58igqmo.fsf@latte.josefsson.org>
333 Subject: Re: target collisions and colliding certificates with different identities
334 Date: Tue, 24 Oct 2006 09:18:50 +0200
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349 Xref: localhost.localdomain rsa-md5:4
354 I am also okay with the proposed license.
359 ----- Original Message -----
360 From: "Simon Josefsson" <jas@extundo.com>
361 To: "Arjen Lenstra" <arjen.lenstra@epfl.ch>
362 Cc: "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl>;
363 <m.m.j.stevens@student.tue.nl>
364 Sent: Tuesday, October 24, 2006 8:43 AM
365 Subject: Re: target collisions and colliding certificates with different
369 > "Arjen Lenstra" <arjen.lenstra@epfl.ch> writes:
373 >> I can't speak for my coauthors, but it's all fine with me, though I
374 >> find the year in your proposed copyright statement a bit odd (I
375 >> would have expected 2006). There are no more authros involved.
377 > Thanks. Duh, I meant 2006, of course. I'd appreciate if Marc and
378 > Benne also replied.
382 >> best regards, Arjen Lenstra
385 >> Arjen K. Lenstra a k l @ e p f l . c h
387 >> INJ 330 (Bâtiment INJ)
389 >> CH-1015 Lausanne, Switzerland
390 >> Tél: + 41 21 693 8101
391 >> Fax: + 41 21 693 7550
395 >> -----Original Message-----
396 >> From: Simon Josefsson [mailto:jas@extundo.com]
397 >> Sent: Tuesday, October 24, 2006 8:28 AM
398 >> To: Weger, B.M.M. de; m.m.j.stevens@student.tue.nl; Arjen Lenstra
399 >> Subject: Re: target collisions and colliding certificates with different
402 >> Great work, thanks!
404 >> I'd like to include your certificates in GnuTLS, a TLS implementation
405 >> that supports X.509, as self-tests of the certificate verification
406 >> logic. Is this OK with you?
408 >> Btw, Gnutls rejected the certificates, we already disable MD5 for
409 >> verification purposes. :)
411 >> For our legal department, I'd like a clarification of the license on
412 >> the data, would you agree to release the certificates under the
413 >> following license?
415 >> Copyright (c) 1996 Marc Stevens, Arjen K. Lenstra, Benne de Weger
417 >> Copying and distribution of this file, with or without modification,
418 >> are permitted in any medium without royalty provided the copyright
419 >> notice and this notice are preserved.
421 >> Also, if any other authors contributed, they would have to agree to
422 >> this license as well. Are there other authors?
424 >> Best regards, and thanks in advance,
427 >> "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl> writes:
432 >>> - an example of a target collision for MD5; this means:
433 >>> for two chosen messages m1 and m2 we have constructed
434 >>> appendages b1 and b2 to make the messages collide
435 >>> under MD5, i.e. MD5(m1||b1) = MD5(m2||b2);
436 >>> said differently: we can cause an MD5 collision for
437 >>> any pair of distinct IHVs;
438 >>> - an example of a pair of valid, unsuspicious X.509
439 >>> certificates with distinct Distinguished Name fields,
440 >>> but identical CA signatures; this example makes use
441 >>> of the target collision.
443 >>> See http://www.win.tue.nl/hashclash/TargetCollidingCertificates/,
444 >>> where the certificates and a more detailed announcement
452 Return-Path: <b.m.m.d.weger@TUE.nl>
453 Received: from yxa.extundo.com ([unix socket])
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476 Subject: RE: target collisions and colliding certificates with different identities
477 Date: Tue, 24 Oct 2006 10:55:38 +0200
478 Message-ID: <DFA3206A564B80499B87B89B49BCD3135DC263@EXCHANGE3.campus.tue.nl>
479 In-Reply-To: <87d58igqmo.fsf@latte.josefsson.org>
481 X-MS-TNEF-Correlator:
482 Thread-Topic: target collisions and colliding certificates with different identities
483 Thread-Index: Acb3N816trM39dt6Tmef1RZSgSRhMQAEdpog
484 From: "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl>
485 To: "Simon Josefsson" <jas@extundo.com>
486 Cc: "Stevens, M.M.J." <M.M.J.Stevens@student.tue.nl>,
487 "Arjen Lenstra" <arjen.lenstra@epfl.ch>
488 X-Spam-Status: No, score=-2.5 required=5.0 tests=AWL,BAYES_00 autolearn=ham
490 X-Spam-Checker-Version: SpamAssassin 3.1.1 (2006-03-10) on yxa-iv
491 X-Virus-Status: Clean
493 Xref: localhost.localdomain rsa-md5:5
497 When your software rejects any MD5 certificate I don't see why
498 you would use our colliding ones, doesn't it mean that you'll=20
499 have more explaining to do?
500 But when you want it this way, it's fine with me too.
505 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
506 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
507 Technische Universiteit Eindhoven
508 Coding & Crypto Groep
509 Faculteit Wiskunde en Informatica
514 tel.: (040) 247 2704, bgg 5141
515 e-mail: b.m.m.d.weger@tue.nl
516 www: http://www.win.tue.nl/~bdeweger
517 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
518 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
523 > -----Original Message-----
524 > From: Simon Josefsson [mailto:jas@extundo.com]=20
525 > Sent: dinsdag 24 oktober 2006 8:44
527 > Cc: Weger, B.M.M. de; Stevens, M.M.J.
528 > Subject: Re: target collisions and colliding certificates=20
529 > with different identities
531 > "Arjen Lenstra" <arjen.lenstra@epfl.ch> writes:
535 > > I can't speak for my coauthors, but it's all fine with me, though I
536 > > find the year in your proposed copyright statement a bit odd (I
537 > > would have expected 2006). There are no more authros involved.
539 > Thanks. Duh, I meant 2006, of course. I'd appreciate if Marc and
540 > Benne also replied.
544 > > best regards, Arjen Lenstra
547 > > Arjen K. Lenstra a k l @ e p f l . c h
549 > > INJ 330 (B=E2timent INJ)
551 > > CH-1015 Lausanne, Switzerland
552 > > T=E9l: + 41 21 693 8101
553 > > Fax: + 41 21 693 7550
557 > > -----Original Message-----
558 > > From: Simon Josefsson [mailto:jas@extundo.com]=20
559 > > Sent: Tuesday, October 24, 2006 8:28 AM
560 > > To: Weger, B.M.M. de; m.m.j.stevens@student.tue.nl; Arjen Lenstra
561 > > Subject: Re: target collisions and colliding certificates=20
562 > with different identities
564 > > Great work, thanks!
566 > > I'd like to include your certificates in GnuTLS, a TLS=20
568 > > that supports X.509, as self-tests of the certificate=20
570 > > logic. Is this OK with you?
572 > > Btw, Gnutls rejected the certificates, we already disable MD5 for
573 > > verification purposes. :)
575 > > For our legal department, I'd like a clarification of the license on
576 > > the data, would you agree to release the certificates under the
577 > > following license?
579 > > Copyright (c) 1996 Marc Stevens, Arjen K. Lenstra,=20
582 > > Copying and distribution of this file, with or without=20
584 > > are permitted in any medium without royalty provided=20
586 > > notice and this notice are preserved.
588 > > Also, if any other authors contributed, they would have to agree to
589 > > this license as well. Are there other authors?
591 > > Best regards, and thanks in advance,
594 > > "Weger, B.M.M. de" <b.m.m.d.weger@TUE.nl> writes:
599 > >> - an example of a target collision for MD5; this means:=20
600 > >> for two chosen messages m1 and m2 we have constructed=20
601 > >> appendages b1 and b2 to make the messages collide=20
602 > >> under MD5, i.e. MD5(m1||b1) =3D MD5(m2||b2);
603 > >> said differently: we can cause an MD5 collision for=20
604 > >> any pair of distinct IHVs;
605 > >> - an example of a pair of valid, unsuspicious X.509=20
606 > >> certificates with distinct Distinguished Name fields,=20
607 > >> but identical CA signatures; this example makes use=20
608 > >> of the target collision.
610 > >> See http://www.win.tue.nl/hashclash/TargetCollidingCertificates/,
611 > >> where the certificates and a more detailed announcement=20
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