Asterisk IAX2 (IAX) POKE Request Saturation Resource Exhaustion Remote DoS

This script is Copyright (C) 2008-2013 Tenable Network Security, Inc.


Synopsis :

The remote VoIP service is susceptible to a remote denial of service
attack.

Description :

The version of Asterisk installed on the remote host consumes an IAX2
call number while waiting for an ACK packet in response to a PONG
packet. By flooding the affected service with POKE requests, an
unauthenticated, remote attacker can leverage this issue to exhaust all
available call numbers and prevent legitimate IAX2 calls from getting
through.

See also :

http://downloads.digium.com/pub/security/AST-2008-010.html
http://www.securityfocus.com/archive/1/494675/30/0/threaded

Solution :

Upgrade to Asterisk Open Source 1.4.21.2 / 1.2.30, Asterisk Business
Edition C.2.0.3 / C.1.10.3 / B.2.5.4, s800i (Asterisk Appliance) 1.2.0.1
or later.

Risk factor :

Medium / CVSS Base Score : 5.0
(CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P)
CVSS Temporal Score : 4.1
(CVSS2#E:F/RL:OF/RC:C)
Public Exploit Available : true

Family: Denial of Service

Nessus Plugin ID: 33576 (asterisk_iax2_poke_exhaust.nasl)

Bugtraq ID: 30321

CVE ID: CVE-2008-3263