CVE-2021-46837 json
res_pjsip_t38 in Sangoma Asterisk 16.x before 16.16.2, 17.x before 17.9.3, and 18.x before 18.2.2, and Certified Asterisk before 16.8-cert7…
published 2022-08-30 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-33492
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.7%
- EPSS 4.7% chance of exploitation in 30 days, percentile 91%
- public exploits
- 0
- none known
Summary
res_pjsip_t38 in Sangoma Asterisk 16.x before 16.16.2, 17.x before 17.9.3, and 18.x before 18.2.2, and Certified Asterisk before 16.8-cert7, allows an attacker to trigger a crash by sending an m=image line and zero port in a response to a T.38 re-invite initiated by Asterisk. This is a re-occurrence of the CVE-2019-15297 symptoms but not for exactly the same reason. The crash occurs because there is an append operation relative to the active topology, but this should instead be a replace operation.
Patch / fix
- digium asterisk 16.16.2, 17.9.3, 18.2.2
- asterisk Debian 14 1:18.9.0~dfsg+~cs6.10.40431411-1
debian advisories DEBIAN-CVE-2021-46837
Exploit prediction
4.67% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Classification
- Weakness
-
- CWE-476 NULL Pointer Dereference
References
-
debian.org
/security/2022/dsa-5285
vendor-advisory, third-party-advisory
-
downloads.asterisk.org
/pub/security/AST-2021-006.html
vendor-advisory
-
lists.debian.org
/debian-lts-announce/2022/11/msg00021.html
mailing-list, third-party-advisory
Sources
- CVE List CVE-2021-46837
- NVD CVE-2021-46837
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