CVE-2021-26712: Digium Asterisk

High severity, CVSS 7.5. EPSS: 3.6% chance of exploitation in the next 30 days.

Incorrect access controls in res_srtp.c in Sangoma Asterisk 13.38.1, 16.16.0, 17.9.1, and 18.2.0 and Certified Asterisk 16.8-cert5 allow a remote unauthenticated attacker to prematurely terminate secure calls by replaying SRTP packets.

Affected products

• Digium Asterisk: from 13.0.0, up to and including 13.38.2; from 16.0.0, before 16.16.1 (fixed in 16.16.1); from 17.0.0, before 17.9.2 (fixed in 17.9.2); from 18.0, before 18.2.1 (fixed in 18.2.1)
• Digium Certified Asterisk: version 16.8 only

Published 2021-02-18. Last modified 2026-06-17.