Home/CVE/A stack-based buffer overflow in res_rtp_asterisk.c in Sangoma Asterisk before 16.16.1, 17.x before 17.9.2, and 18.x bef
CVE

CVE-2021-26713

A stack-based buffer overflow in res_rtp_asterisk.c in Sangoma Asterisk before 16.16.1, 17.x before 17.9.2, and 18.x bef

A stack-based buffer overflow in res_rtp_asterisk.c in Sangoma Asterisk before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6 allows an authenticated WebRTC client to cause an Asterisk crash by sending multiple hold/unhold requests in quick succession. This is caused by a signedness comparison mismatch.

MEDIUM · CVSS 6.5 EPSS 0.00128
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-787Out-of-bounds Write
▤

Affected Products & Versions

4
digium asterisk>= 16.0.0 and < 16.16.1
digium asterisk>= 17.0.0 and < 17.9.2
digium asterisk>= 18.0.0 and < 18.2.1
digium certified asteriskall versions
▣

Scoring & Timeline

6.5
MEDIUM · 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 NVD19 Feb 2021 · 08:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
🔗

References & Sources

3
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://downloads.asterisk.org/pub/security/Vendor Advisory
https://downloads.asterisk.org/pub/security/AST-2021-004.htmlVendor Advisory
https://issues.asterisk.org/jira/browse/ASTERISK-29205Vendor Advisory
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