Asterisk Project Security Advisory - AST-2016-007
Product Asterisk
Summary RTP Resource Exhaustion
Nature of Advisory Denial of Service
Susceptibility Remote Authenticated Sessions
Severity Moderate
Exploits Known No
Reported On August 5, 2016
Reported By Etienne Lessard
Posted On
Last Updated On September 8, 2016
Advisory Contact Joshua Colp <jcolp AT digium DOT com>
CVE Name
Description The overlap dialing feature in chan_sip allows chan_sip to
report to a device that the number that has been dialed is
incomplete and more digits are required. If this
functionality is used with a device that has performed
username/password authentication RTP resources are leaked.
This occurs because the code fails to release the old RTP
resources before allocating new ones in this scenario. If
all resources are used then RTP port exhaustion will occur
and no RTP sessions are able to be set up.
Resolution If overlap dialing support is not needed the â??allowoverlapâ??
option can be set to no. This will stop any usage of the
scenario which causes the resource exhaustion.
If overlap dialing support is needed a change has been made
so that existing RTP resources are destroyed in this
scenario before allocating new resources.
Affected Versions
Product Release
Series
Asterisk Open Source 11.x All Versions
Asterisk Open Source 13.x All Versions
Certified Asterisk 11.6 All Versions
Certified Asterisk 13.8 All Versions
Corrected In
Product Release
Asterisk Open Source 11.23.1, 13.11.1
Certified Asterisk 11.6-cert15, 13.8-cert3
Patches
SVN URL Revision
Links https://issues.asterisk.org/jira/browse/ASTERISK-26272
Asterisk Project Security Advisories are posted at
http://www.asterisk.org/security
This document may be superseded by later versions; if so, the latest
version will be posted at
http://downloads.digium.com/pub/security/AST-2016-007.pdf and
http://downloads.digium.com/pub/security/AST-2016-007.html
Revision History
Date Editor Revisions Made
August 23, 2016 Joshua Colp Initial creation
Asterisk Project Security Advisory - AST-2016-007
Copyright © 2016 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.
