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

medium Nessus Plugin ID 33576
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The remote VoIP service is susceptible to a remote denial of service attack.


The version of Asterisk running 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.


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

See Also

Plugin Details

Severity: Medium

ID: 33576

File Name: asterisk_iax2_poke_exhaust.nasl

Version: 1.19

Type: remote

Published: 7/25/2008

Updated: 11/15/2018

Dependencies: iax2_detection.nasl

Risk Information


Risk Factor: Medium

Score: 4.4


Risk Factor: Medium

Base Score: 5

Temporal Score: 3.9

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: E:POC/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:asterisk:asterisk

Required KB Items: Services/udp/iax2

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 7/22/2008

Reference Information

CVE: CVE-2008-3263

BID: 30321

Secunia: 31178

CWE: 399