key ID 57E37087 vs BA8F038D

[johnhectorfrink]

I have downloaded KNOPPIX_V4.0.2DVD-2005-09-23-EN.iso and the corresponding
md5, sha1, and asc files via:

http://knopper.net/knoppix-mirrors/download.php?lang=en&link=rsync://ftp.uni-kl.de/knoppix-dvd

When I use gpg, I get this information (after I have retreived the identified key):

gpg: Signature made Sat Sep 24 15:59:30 2005 NZST using DSA key ID 57E37087
gpg: Good signature from "Klaus Knopper <knopper@knopper.net>"
gpg: aka "Klaus Knopper <info@knopper.net>"
gpg: aka "Klaus Knopper <knoppix@knopper.net>"
gpg: WARNING: This key is not certified with a trusted signature!
gpg: There is no indication that the signature belongs to the owner.
Primary key fingerprint: 0E57 3DA0 F139 69EF 1DD5 ACAA 3798 E3D7 57E3 7087

Now, the Downloading FAQ leads me to expect a key ID of BA8F038D.

So, what is the story here?

[gregk]

On trying to verify KNOPPIX_V5.1.1DVD-2007-01-04-EN.iso.md5.asc I also get DSA key ID 57E37087 - not the expected one. Would really like to know what's going on here...

[gregk]

going to keyserver.net and looking for knoppix lists:

Klaus Knopper <knopper@knopper.net> 0x57E37087 1024/1024 2000/05/06 Never

So apparently somebody claiming to be Klaus registered that key back in 2000. Still it's odd that there are so few references to that key on the net.

[mennucc1]

In my gpg keyring, it appears that
key BA8F038D is signed by key 57E37087 ;
but key 57E37087 is not signed by key BA8F038D.

Moreover,
$ gpg --verify KNOPPIX_V5.1.1DVD-2007-01-04-EN.iso.md5.asc
gpg: Signature made ven 05 gen 2007 04:15:35 CET using DSA key ID 57E37087
gpg: Good signature from "Klaus Knopper <knopper@knopper.net>"
gpg: aka "Klaus Knopper <info@knopper.net>"
gpg: aka "Klaus Knopper <knoppix@knopper.net>"
gpg: WARNING: This key is not certified with a trusted signature!
gpg: There is no indication that the signature belongs to the owner.
Primary key fingerprint: 0E57 3DA0 F139 69EF 1DD5 ACAA 3798 E3D7 57E3 7087

So, verifying the downloaded image by using key 57E37087 does not provide any security at all.

I could imagine a situation like this:
Mr Knopper builds Knoppix and signs the image with key BA8F038D ;
the attacker creates a key 57E37087 and it signs BA8F038D with it,
the attacker tampers Knoppix and signs with 57E37087.

I know this sounds a bit paranoid; but I will feel safer if Mr Knopper may post the gpg fingerprint of both keys in the FAQ.