OpenSSH S/KEY Authentication Account Enumeration

This script is Copyright (C) 2011 Tenable Network Security, Inc.


Synopsis :

The remote host is susceptible to an information disclosure attack.

Description :

When OpenSSH has S/KEY authentication enabled, it is possible to
determine remotely if an account configured for S/KEY authentication
exists.

Note that Nessus has not tried to exploit the issue, but rather only
checked if OpenSSH is running on the remote host. As a result, it
will not detect if the remote host has implemented a workaround.

See also :

http://www.nessus.org/u?87921f08

Solution :

A patch currently does not exist for this issue. As a workaround,
either set 'ChallengeResponseAuthentication' in the OpenSSH config to
'no' or use a version of OpenSSH without S/KEY support compiled in.

Risk factor :

Medium / CVSS Base Score : 5.0
(CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N)
CVSS Temporal Score : 4.8
(CVSS2#E:F/RL:U/RC:ND)
Public Exploit Available : true

Family: Misc.

Nessus Plugin ID: 17704 ()

Bugtraq ID: 23601

CVE ID: CVE-2007-2243