The IAX2 channel driver (chan_iax2) in Asterisk before 1.2.22 and 1.4.x before 1.4.8, Business Edition before B.2.2.1, AsteriskNOW before beta7, Appliance Developer Kit before 0.5.0, and s800i before 1.0.2 allows remote attackers to cause a denial of service (crash) via a crafted (1) LAGRQ or (2) LAGRP frame that contains information elements of IAX frames, which results in a NULL pointer dereference when Asterisk does not properly set an associated variable.

The STUN implementation in Asterisk 1.4.x before 1.4.8, AsteriskNOW before beta7, Appliance Developer Kit before 0.5.0, and s800i before 1.0.2 allows remote attackers to cause a denial of service (crash) via a crafted STUN length attribute in a STUN packet sent on an RTP port.

The Skinny channel driver (chan_skinny) in Asterisk before 1.2.22 and 1.4.x before 1.4.8, Business Edition before B.2.2.1, AsteriskNOW before beta7, Appliance Developer Kit before 0.5.0, and s800i before 1.0.2 allows remote attackers to cause a denial of service (crash) via a certain data length value in a crafted packet, which results in an "overly large memcpy."

The Manager Interface in Asterisk before 1.2.18 and 1.4.x before 1.4.3 allows remote attackers to cause a denial of service (crash) by using MD5 authentication to authenticate a user that does not have a password defined in manager.conf, resulting in a NULL pointer dereference.

The handle_response function in chan_sip.c in Asterisk before 1.2.17 and 1.4.x before 1.4.2 allows remote attackers to cause a denial of service (crash) via a SIP Response code 0 in a SIP packet.

Asterisk 1.4 before 1.4.1 and 1.2 before 1.2.16 allows remote attackers to cause a denial of service (crash) by sending a Session Initiation Protocol (SIP) packet without a URI and SIP-version header, which results in a NULL pointer dereference.

Unspecified vulnerability in the SIP channel driver (channels/chan_sip.c) in Asterisk 1.2.x before 1.2.13 and 1.4.x before 1.4.0-beta3 allows remote attackers to cause a denial of service (resource consumption) via unspecified vectors that result in the creation of "a real pvt structure" that uses more resources than necessary.

Integer overflow in the get_input function in the Skinny channel driver (chan_skinny.c) in Asterisk 1.0.x before 1.0.12 and 1.2.x before 1.2.13, as used by Cisco SCCP phones, allows remote attackers to execute arbitrary code via a certain dlen value that passes a signed integer comparison and leads to a heap-based buffer overflow.

Stack-based buffer overflow in channels/chan_mgcp.c in MGCP in Asterisk 1.0 through 1.2.10 allows remote attackers to execute arbitrary code via a crafted audit endpoint (AUEP) response.

The IAX2 channel driver (chan_iax2) for Asterisk 1.2.x before 1.2.9 and 1.0.x before 1.0.11 allows remote attackers to cause a denial of service (crash) and execute arbitrary code via truncated IAX 2 (IAX2) video frames, which bypasses a length check and leads to a buffer overflow involving negative length check. NOTE: the vendor advisory claims that only a DoS is possible, but the original researcher is reliable.