CVE-2021-46837
mediumpriority · track · 28EPSS 0.047 · 92 %ileEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (8)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
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references (11)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2021-46837/cnnvd
- https://downloads.asterisk.org/pub/security/AST-2021-006.htmlcnnvd
- https://lists.debian.org/debian-lts-announce/2022/11/msg00021.htmlcnnvd
- https://packetstormsecurity.com/files/169938/Debian-Security-Advisory-5285-1.htmlcnnvd
- https://www.debian.org/security/2022/dsa-5285cnnvd
- https://downloads.asterisk.org/pub/security/AST-2021-006.htmlenisa_euvd
- https://lists.debian.org/debian-lts-announce/2022/11/msg00021.htmlenisa_euvd
- https://www.debian.org/security/2022/dsa-5285enisa_euvd
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