The IAX2 protocol implementation in Asterisk Open Source 1.0.x, 1.2.x before 1.2.30, and 1.4.x before 1.4.21.2; Business Edition A.x.x, B.x.x before B.2.5.4, and C.x.x before C.1.10.3; AsteriskNOW; Appliance Developer Kit 0.x.x; and s800i 1.0.x before 1.2.0.1 allows remote attackers to cause a denial of service (call-number exhaustion and CPU consumption) by quickly sending a large number of IAX2 (IAX) POKE requests.

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.

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.

Integer signedness error in format_jpeg.c in Asterisk 1.2.6 and earlier allows remote attackers to execute arbitrary code via a length value that passes a length check as a negative number, but triggers a buffer overflow when it is used as an unsigned length.

Directory traversal vulnerability in vmail.cgi in Asterisk 1.0.9 through 1.2.0-beta1 allows remote attackers to access WAV files via a .. (dot dot) in the folder parameter.