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CVE Request for OpenSSH vulnerability - authentication limits bypass


From: king cope <isowarez.isowarez.isowarez () googlemail com>
Date: Tue, 21 Jul 2015 11:16:35 +0200

Hello list, solar designer,

Can you please add a CVE for the mentioned vulnerability in OpenSSH.

The OpenSSH server normally wouldn't allow successive authentications
that exceed the MaxAuthTries setting in sshd_config,
with this vulnerability the allowed login retries can be extended
limited only by the LoginGraceTime setting,
that can be more than 10000 tries (depends on the network speed), and
even more for local attacks. Technically this vulnerability affects
OpenSSH. It can be found with FreeBSD installations because these use
the keyboard-interactive authentication
mechanism (that is the one affected) in combination with pam. I
haven't tested skey/bsd auth.
To note that this vulnerability looks pretty old, a test against
FreeBSD 6.2 (2007 release date) showed it vulnerable.
Additionally there is no delay between the authentication retries, but
this is another issue that makes this vulnerability more effective.

CVE please!

Thank you,

KC

Reference: http://seclists.org/fulldisclosure/2015/Jul/92


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