Asterisk SIP File Descriptor Exhaustion with chan_sip Session-Timers DoS (AST-2014-002)

This script is Copyright (C) 2014 Tenable Network Security, Inc.


Synopsis :

The version of Asterisk installed on the remote host may be affected by
a denial of service vulnerability.

Description :

According to the version in its SIP banner, the version of Asterisk
running on the remote host is potentially affected by a denial of
service vulnerability.

A denial of service flaw exists with the SIP INVITE request handling.
It is possible for a remote attacker to use all available file
descriptors using SIP INVITE requests. These file descriptors cannot be
released without restarting Asterisk, which could allow an attacker to
bypass intrusion detection systems.

Note that Nessus has not tested for this issue, but instead has relied
only on the application's self-reported version number.

See also :

http://www.nessus.org/u?0688704f
http://downloads.asterisk.org/pub/security/AST-2014-002.html
https://issues.asterisk.org/jira/browse/ASTERISK-23373

Solution :

Upgrade to Asterisk 1.8.26.1 / 11.8.1 / 12.1.1 / Certified Asterisk
1.8.15-cert5 / 11.6-cert2, or apply the appropriate patch listed in the
Asterisk advisory.

Risk factor :

Medium / CVSS Base Score : 4.3
(CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P)
CVSS Temporal Score : 3.7
(CVSS2#E:ND/RL:OF/RC:C)
Public Exploit Available : false

Family: Misc.

Nessus Plugin ID: 73020 ()

Bugtraq ID: 66094

CVE ID: CVE-2014-2287