Intrusion Prevention

Digium.Asterisk.SIP.Terminated.Channel.ACK.SDP.DoS

Description

This indicates an attack attempt to exploit a Denial of Service vulnerability in Asterisk Open Source and Certified Asterisk.
The vulnerability is due to an error when the SIP channel driver fails to properly handle an ACK with SDP received after the channel has been terminated. A remote attacker may be able to exploit this to cause a denial of service condition on the affected system.

Affected Products

Digium Asterisk Open Source Prior to 1.8.23.1
Digium Asterisk Open Source Prior to 11.5.1
Digium Certified Asterisk Prior to 1.8.15-cert3
Digium Certified Asterisk Prior to 11.2-cert2

Impact

Denial of Service: Remote attackers can crash vulnerable systems or services

Recommended Actions

Apply the most recent upgrade or patch from the vendor.
http://downloads.asterisk.org/pub/security/AST-2013-004.html

CVE References

CVE-2013-5641