Asterisk IAX2 Multiple Method Handshake Spoofing DoS

Medium Nessus Plugin ID 32132


The remote VoIP service can be abused to conduct an amplification attack against third-party hosts.


The version of Asterisk running on the remote host does not properly validate an IAX2 handshake. By spoofing NEW and ACK messages, an unauthenticated, remote attacker may be able to leverage this issue to flood a third-party host with packets from the affected host containing audio data.


Upgrade to Asterisk 1.4.20 / 1.2.28, Asterisk Business Edition C.1.8.1 / B.2.5.2, AsteriskNOW 1.0.3, s800i (Asterisk Appliance) or later.

See Also

Plugin Details

Severity: Medium

ID: 32132

File Name: asterisk_iax2_spoofed_handshake.nasl

Version: 1.21

Type: remote

Published: 2008/05/06

Updated: 2018/11/15

Dependencies: 20834

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:asterisk:open_source

Required KB Items: Services/udp/iax2

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2008/04/22

Reference Information

CVE: CVE-2008-1897, CVE-2008-1923

BID: 28901

Secunia: 29927

CWE: 16, 287