Kerberos telnet Crafted Username Remote Authentication Bypass

This script is Copyright (C) 2007-2013 Tenable Network Security, Inc.


Synopsis :

It is possible to log into the remote system using telnet without
supplying any credentials

Description :

The remote version of Kerberos telnet does not sanitize the
user-supplied 'USER' environement variable. By supplying a specially
malformed USER environment variable, an attacker may force the remote
telnet server to believe that the user has already authenticated.

Solution :

Apply the patch below or contact your vendor for a patch :

http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2007-001-telnetd.txt

Risk factor :

High / CVSS Base Score : 7.6
(CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C)
CVSS Temporal Score : 6.3
(CVSS2#E:F/RL:OF/RC:C)
Public Exploit Available : true

Family: Gain a shell remotely

Nessus Plugin ID: 24998 (krb_telnet_env.nasl)

Bugtraq ID: 23281

CVE ID: CVE-2007-0956