Description
Asterisk is an open source private branch exchange and telephony toolkit. Prior to Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3, an authenticated attacker may crash Asterisk through a buffer over-read in the `PJSIP MWI body parser` by sending a carefully crafted `SIP NOTIFY` request. The attacker must pass SIP authentication using either a username/password or `source IP address matching`. This issue is fixed in Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3.
References10
- github.com/asterisk/asterisk/commit/07aec894a1fdfa7fa989d3ab40f…
- github.com/asterisk/asterisk/commit/1039bed76fa3248f58b6880e4b3…
- github.com/asterisk/asterisk/commit/1b2d99d8eb9206d37fd47115996…
- github.com/asterisk/asterisk/commit/3100a0d331affbf0995b8c57aad…
- github.com/asterisk/asterisk/commit/57ce484a45b098de417f19265c9…
- github.com/asterisk/asterisk/commit/919f2ffda03329c9014bedcb3c7…
- github.com/asterisk/asterisk/commit/dafff9fb60281817225f1ce6371…
- github.com/asterisk/asterisk/releases/tag/20.20.1
- github.com/asterisk/asterisk/releases/tag/21.12.3
- github.com/asterisk/asterisk/releases/tag/22.10.1
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 5 November 2026
- CWE
- CWE-126CWE-170
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.