CVE-2025-57767: Sangoma Asterisk

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Asterisk is an open source private branch exchange and telephony toolkit. Prior to versions 20.15.2, 21.10.2, and 22.5.2, if a SIP request is received with an Authorization header that contains a realm that wasn't in a previous 401 response's WWW-Authenticate header, or an Authorization header with an incorrect realm was received without a previous 401 response being sent, the get_authorization_header() function in res_pjsip_authenticator_digest will return a NULL. This wasn't being checked before attempting to get the digest algorithm from the header which causes a SEGV. This issue has been patched in versions 20.15.2, 21.10.2, and 22.5.2. There are no workarounds.

Affected products

• Sangoma Asterisk: before 20.15.2 (fixed in 20.15.2); from 21.0.0, before 21.10.2 (fixed in 21.10.2); from 22.0.0, before 22.5.2 (fixed in 22.5.2)

Published 2025-08-28. Last modified 2026-06-17.