Asterisk Project Security Advisory - AST-2014-014 Product Asterisk Summary High call load may result in hung channels in ConfBridge. Nature of Advisory Denial of Service Susceptibility Remote Unauthenticated Sessions Severity Moderate Exploits Known No Reported On 19 October, 2014 Reported By Ben Klang Posted On 20 November 2014 Last Updated On November 20, 2014 Advisory Contact Joshua Colp <jcolp AT digium DOT com> CVE Name Pending Description The ConfBridge application uses an internal bridging API to implement conference bridges. This internal API uses a state model for channels within the conference bridge and transitions between states as different things occur. Under load it is possible for some state transitions to be delayed causing the channel to transition from being hung up to waiting for media. As the channel has been hung up remotely no further media will arrive and the channel will stay within ConfBridge indefinitely. Resolution The underlying bridging code that ConfBridge uses has been fixed so state changes can not occur that will take a channel out of the hung up state. Affected Versions Product Release Series Asterisk Open Source 11.x All versions Certified Asterisk 11.6 All versions Corrected In Product Release Asterisk Open Source 11.14.1 Certified Asterisk 11.6-cert8 Patches SVN URL Revision http://downloads.asterisk.org/pub/security/AST-2014-014-11.diff Asterisk 11 http://downloads.asterisk.org/pub/security/AST-2014-014-11.6.diff Certified Asterisk 11.6 Links https://issues.asterisk.org/jira/browse/ASTERISK-24440 Asterisk Project Security Advisories are posted at http://www.asterisk.org/security This document may be superseded by later versions; if so, the latest version will be posted at http://downloads.digium.com/pub/security/AST-2014-014.pdf and http://downloads.digium.com/pub/security/AST-2014-014.html Revision History Date Editor Revisions Made 20 November, 2014 Joshua Colp Initial Advisory created Asterisk Project Security Advisory - AST-2014-014 Copyright (c) 2014 Digium, Inc. All Rights Reserved. Permission is hereby granted to distribute and publish this advisory in its original, unaltered form.