CVE-2016-2161: Apache HTTP Server

High severity, CVSS 7.5. EPSS: 21% chance of exploitation in the next 30 days.

In Apache HTTP Server versions 2.4.0 to 2.4.23, malicious input to mod_auth_digest can cause the server to crash, and each instance continues to crash even for subsequently valid requests.

Affected products

• Apache HTTP Server: version 2.4.0 only; version 2.4.1 only; version 2.4.2 only; version 2.4.3 only; version 2.4.6 only; version 2.4.7 only; …

Published 2017-07-27. Last modified 2026-06-17.