Medium severity · published Aug 30, 2022
CVE-2021-46837
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…
6.5
CVSS
4.7%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.7% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Asterisk · Digium
16.0.0 before 16.16.2; 17.0.0 before 17.9.3; 18.0.0 before 18.2.2 · source: NVD
CA
Certified Asterisk · Asterisk
16.8.0; 16.8.0; 16.8.0; 16.8.0; 16.8.0; 16.8.0; +1 more · source: NVD
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-46837
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-46837
Vendor Advisory
https://downloads.asterisk.org/pub/security/AST-2021-006.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/11/msg00021.html
Third Party Advisory
https://www.debian.org/security/2022/dsa-5285
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