Vulnerability 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 unbounded `sscanf` in `res_pjsip_pubsub` when parsing the `MWI NOTIFY` `Message-Account` field may allow an unauthenticated attacker to send a carefully crafted packet that causes a stack buffer overflow and corrupts the underlying transport, permanently disabling all SIP functionality. An Asterisk restart is required to restore full operation. 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.
Related Weaknesses (CWE)
References
- https://github.com/asterisk/asterisk/commit/0e89514084490070c5ecee419ec5ee37b7c4
- https://github.com/asterisk/asterisk/commit/647b35c3cfd4a2cc3b1fb7560b085feba5c2
- https://github.com/asterisk/asterisk/commit/7a1ffcdf38cc76d1c4eae51651667f3fd454
- https://github.com/asterisk/asterisk/commit/b4be3bd67ce4ac35b94fbfa860cdd9e1c906
- https://github.com/asterisk/asterisk/commit/b5281828dad7d44658439ba6393fe6be3328
- https://github.com/asterisk/asterisk/commit/dca516f6d895e8867d48fa56b6ce7f05b6f7
- https://github.com/asterisk/asterisk/commit/ee1b66a5e40733ba0b9fad7fc4d032cabbe1
- https://github.com/asterisk/asterisk/releases/tag/20.20.1
- https://github.com/asterisk/asterisk/releases/tag/21.12.3
- https://github.com/asterisk/asterisk/releases/tag/22.10.1
- https://github.com/asterisk/asterisk/releases/tag/23.4.1
- https://github.com/asterisk/asterisk/releases/tag/certified-20.7-cert11
- https://github.com/asterisk/asterisk/releases/tag/certified-22.8-cert3
- https://github.com/asterisk/asterisk/security/advisories/GHSA-589g-qgf8-m6mx
- https://github.com/asterisk/asterisk/tree/24.0.0-pre1
FAQ
What is CVE-2026-57191?
CVE-2026-57191 is a documented vulnerability. 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 unbounded `sscanf` in `...
How severe is CVE-2026-57191?
CVSS scoring is not yet available for CVE-2026-57191. Check NVD for updates.
Is there a patch for CVE-2026-57191?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.