CVE-2021-31878: Digium Asterisk

Medium severity, CVSS 6.5. EPSS: 2.5% chance of exploitation in the next 30 days.

An issue was discovered in PJSIP in Asterisk before 16.19.1 and before 18.5.1. To exploit, a re-INVITE without SDP must be received after Asterisk has sent a BYE request.

Affected products

• Digium Asterisk: version 16.17.0 only; version 16.18.0 only; version 16.19.0 only; version 18.3.0 only; version 18.4.0 only; version 18.5.0 only

Published 2021-07-30. Last modified 2026-06-17.