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Home >> Browse Vulnerability Assessment Database >> Gain root remotely >> Solaris 10 Telnet Authentication Bypass

Vulnerability Assessment Details

Solaris 10 Telnet Authentication Bypass

Vulnerability Assessment Summary
Attempts to log in as -fbin

Detailed Explanation for this Vulnerability Assessment

Summary :

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

Description :

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

For instance, the following command :

telnet -l '-fbin' targethost

Will result in obtaining a shell with the rights of the 'bin'
user.

Solution :

Install patches 120068-02 (sparc) or 120069-02 (i386)
which are available from Sun.

Filter incoming to this port or disable the telnet service
and use SSH instead, or use inetadm to mitigate this
problem (see the link below).

See also :

http://lists.sans.org/pipermail/list/2007-February/025935.html
http://isc.sans.org/diary.html?storyid=2220

Network Security Threat Level:

Critical / CVSS Base Score : 10
(AV:R/AC:L/Au:NR/C:C/I:C/A:C/B:N)

Networks Security ID: 22512

Vulnerability Assessment Copyright: This script is Copyright (C) 2007 Tenable Network Security, Inc.

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