channels/chan_sip.c in Asterisk Open Source 1.8.x before 1.8.26.1, 11.8.x before 11.8.1, and 12.1.x before 12.1.1, and Certified Asterisk 1.8.15 before 1.8.15-cert5 and 11.6 before 11.6-cert2, when chan_sip has a certain configuration, allows remote authenticated users to cause a denial of service (channel and file descriptor consumption) via an INVITE request with a (1) Session-Expires or (2) Min-SE header with a malformed or invalid value.
https://issues.asterisk.org/jira/browse/ASTERISK-23373
http://www.securityfocus.com/bid/66094
http://www.mandriva.com/security/advisories?name=MDVSA-2014:078
http://lists.fedoraproject.org/pipermail/package-announce/2014-March/130426.html
http://lists.fedoraproject.org/pipermail/package-announce/2014-March/130400.html
http://downloads.asterisk.org/pub/security/AST-2014-002.html
http://downloads.asterisk.org/pub/security/AST-2014-002-1.8.diff