Digium Asterisk SIP Terminated Channel ACK with SDP Denial of Service (CVE-2013-5641)
|Check Point Reference:||CPAI-2013-3492|
|Source:||Digium Advisory AST-2013-004|
|Protection Provided by:||
Who is Vulnerable?
Digium Asterisk Open Source Prior to 22.214.171.124
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
A denial of service vulnerability exists in Asterisk Open Source and Certified Asterisk.
The vulnerability is due to the SIP channel driver failing to properly handle an ACK with SDP received after the channel has been terminated. A remote attacker could exploit this vulnerability by sending a delayed ACK request with SDP to the vulnerable server. Successful exploitation would result in a denial of service condition.
This protection will detect and block attempts to exploit this vulnerability.
In order for the protection to be activated, update your product to the latest update. For information on how to update , go to SBP-2006-05, Protection tab and select the version of your choice.
To configure the defense, select your product from the list below and follow the related protection steps.
Security Gateway R75 / R71 / R70
How Can I Protect My Network?
- In the IPS tab, click Protections and find the Digium Asterisk SIP Terminated Channel ACK with SDP Denial of Service protection using the Search tool and Edit the protection's settings.
- Install policy on all modules.
How Do I Know if My Network is Under Attack?
SmartView Tracker will log the following entries:
Attack Name: VoIP Enforcement Violation
Attack Information: Digium Asterisk SIP Terminated Channel ACK with SDP Denial of Service