Samba Symlink Traversal Arbitrary File Access (unsafe check)

This script is Copyright (C) 2010-2012 Tenable Network Security, Inc.


Synopsis :

The remote file server is prone to a symlink attack.

Description :

The remote Samba server is configured insecurely and allows a remote
attacker to gain read or possibly write access to arbitrary files on
the affected host. Specifically, if an attacker has a valid Samba
account for a share that is writable or there is a writable share that
is configured to be a guest account share, he can create a symlink
using directory traversal sequences and gain access to files and
directories outside that share.

Note that successful exploitation requires that the Samba server's
'wide links' parameter be set to 'yes', which is the default.

See also :

http://archives.neohapsis.com/archives/fulldisclosure/2010-02/0100.html
http://www.youtube.com/watch?v=NN50RtZ2N74
http://www.samba.org/samba/news/symlink_attack.html

Solution :

Set 'wide links = no' in the [global] section of smbd.conf.

Risk factor :

High / CVSS Base Score : 7.5
(CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P)
CVSS Temporal Score : 6.2
(CVSS2#E:F/RL:OF/RC:C)
Public Exploit Available : true

Family: Misc.

Nessus Plugin ID: 44406 ()

Bugtraq ID: 38111

CVE ID: CVE-2010-0926