Home/CVE/An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certifie
CVE

CVE-2021-26717

An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certifie

An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.

HIGH · CVSS 7.5 EPSS 0.00421
Act now
  • Public exploit or PoC is available
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
▤

Affected Products & Versions

4
digium asterisk>= 16.0.0 and < 16.16.1
digium asterisk>= 17.0.0 and < 17.9.2
digium asterisk>= 18.0 and < 18.2.1
digium certified asteriskall versions
⚠

Public Exploits & PoCs

1
pocpacketstormsecurity.com · Asterisk-Project-Security-Advisory-AST-2021-002.htmlpacketstormsecurity.com
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD18 Feb 2021 · 08:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
🔗

References & Sources

4
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
http://seclists.org/fulldisclosure/2021/Feb/58Mailing ListPatchThird Party Advisory
https://downloads.asterisk.org/pub/security/Vendor Advisory
https://downloads.asterisk.org/pub/security/AST-2021-002.htmlVendor Advisory
https://issues.asterisk.org/jira/browse/ASTERISK-29203Issue TrackingPatchVendor Advisory
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