Bug 63995 – app-admin/skey-1.1.5-r2: change of MD5 back to MD4

• Status: RESOLVED FIXED
• Product: Gentoo Security

[Description Ulrich Müller 2004-09-14 07:12:50 UTC]

I was wondering about the change of the default algorithm used
by S/Key introduced in version 1.1.5-r1: The algorithm used in
vanilla 1.1.5 is MD5, and that is what is suggested as the default
in RFC 2289, while MD4 is now purely optional:

| All conforming implementations of both server and generators MUST
| support MD5. They SHOULD support SHA and MAY also support MD4.

Now in -r1 (and still in -r2) the patch by skey-1.1.5-gentoo.diff
changes that default from MD5 (back?) to MD4.

I wonder if this isn't a step in the wrong direction, considering
RFC 2289 and <http://www.rsasecurity.com/rsalabs/node.asp?id=2253>:

| Dobbertin [Dob 95] has shown how collisions for the full version of
| MD4 can be found in under a minute on a typical PC. In recent work,
| Dobbertin (Fast Software Encryption, 1998) has shown that a reduced
| version of MD4 in which the third round of the compression function
| is not executed but everything else remains the same, is not
| one-way. Clearly, MD4 should now be considered broken.

[Comment 1 Thierry Carrez (RETIRED) 2004-09-14 07:20:37 UTC]

Tavis, please comment, as you were the one that committed the changes in -r1 about... 1 year ago :)

[Comment 2 Tavis Ormandy (RETIRED) 2004-09-14 07:50:47 UTC]

I had completely forgotten about this, I think it was the reporter who emailed a few months ago about it. He's quite correct, the default should be changed to md5. it's a simple fix, and app-admin/skey-1.1.5-r3 includes it.

[Comment 3 Thierry Carrez (RETIRED) 2004-09-14 08:20:49 UTC]

Does everyone agree with me it should be closed without GLSA ?

[Comment 4 Thierry Carrez (RETIRED) 2004-09-14 08:31:22 UTC]

Ebuild should be stable before this is closed.

Target keywords : x86 ppc sparc mips alpha arm hppa amd64 ia64 s390 ppc64
Arches please test app-admin/skey-1.1.5-r3 and mark stable.

[Comment 5 Guy Martin (RETIRED) 2004-09-14 08:47:00 UTC]

Done on hppa.

[Comment 6 Olivier Crete (RETIRED) 2004-09-14 16:12:14 UTC]

stable on x86
btw repoman reminds us that app-admin/skey/files/skey-1.1.5-gentoo.diff.gz is 37k.. that is bigger than 20k..

[Comment 7 Pieter Van den Abeele (RETIRED) 2004-09-14 17:29:34 UTC]

stable on ppc

[Comment 8 Jason Wever (RETIRED) 2004-09-15 05:14:38 UTC]

Stable on sparc

[Comment 9 Bryan Østergaard (RETIRED) 2004-09-15 17:34:17 UTC]

Stable on alpha.

[Comment 10 SpanKY 2004-09-19 17:53:52 UTC]

only s390 left ...

[Comment 11 Thierry Carrez (RETIRED) 2004-09-20 05:43:14 UTC]

Closing without GLSA

[Comment 12 SpanKY 2004-09-22 20:51:06 UTC]

s390 is done