CVE-2008-3903: Asterisk P B X

Low severity, CVSS 3.5. EPSS: 1.9% chance of exploitation in the next 30 days.

Asterisk Open Source 1.2.x before 1.2.32, 1.4.x before 1.4.24.1, and 1.6.0.x before 1.6.0.8; Asterisk Business Edition A.x.x, B.x.x before B.2.5.8, C.1.x.x before C.1.10.5, and C.2.x.x before C.2.3.3; s800i 1.3.x before 1.3.0.2; and Trixbox PBX 2.6.1, when Digest authentication and authalwaysreject are enabled, generates different responses depending on whether a SIP username is valid, which allows remote attackers to enumerate valid usernames.

Affected products

• Asterisk P B X: version 1.2 only; version 1.2.22 only; version 1.4.21.1 only; version 1.6 only
• Trixbox Pbx: version 2.6.1 only

Published 2008-09-04. Last modified 2026-06-16.