CVE-2011-2665: Digium Asterisk

Medium severity, CVSS 5.0. EPSS: 4% chance of exploitation in the next 30 days.

reqresp_parser.c in the SIP channel driver in Asterisk Open Source 1.8.x before 1.8.4.3 allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a SIP packet with a Contact header that lacks a < (less than) character.

Affected products

• Digium Asterisk: version 1.8.0 only; version 1.8.1 only; version 1.8.1.1 only; version 1.8.1.2 only; version 1.8.2 only; version 1.8.2.1 only; …

Published 2011-07-06. Last modified 2026-06-16.