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 before 18.2.1 and Certified Asterisk before 16.8-cert6 allows an authenticated WebRTC client to cause an Asterisk crash by sending…
Does this matter?
Lower severity and a low EPSS score (1.87%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.87% probability · 79th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- digium/asterisk · digium/certified asterisk
- Source
- cve@mitre.org
EPSS 1.9% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- 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
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.