Description
The SIP channel driver in Asterisk Open Source 1.2.x before 1.2.34, 1.4.x before 1.4.26.1, 1.6.0.x before 1.6.0.12, and 1.6.1.x before 1.6.1.4; Asterisk Business Edition A.x.x, B.x.x before B.2.5.9, C.2.x before C.2.4.1, and C.3.x before C.3.1; and Asterisk Appliance s800i 1.2.x before 1.3.0.3 does not use a maximum width when invoking sscanf style functions, which allows remote attackers to cause a denial of service (stack memory consumption) via SIP packets containing large sequences of ASCII decimal characters, as demonstrated via vectors related to (1) the CSeq value in a SIP header, (2) large Content-Length value, and (3) SDP.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | asterisk | 1:1.6.2.0~dfsg~rc1-1 | — |
References
- http://labs.mudynamics.com/advisories/MU-200908-01.txt
- ADV-2009-2229 vdb-entry
- http://downloads.digium.com/pub/security/AST-2009-005.html
- 36015 vdb-entry
- 20090811 AST-2009-005: Remote Crash Vulnerability in SIP channel driver mailing-list
- 1022705 vdb-entry
- 36227 third-party-advisory