CVE-2011-3348: Apache HTTP Server

Medium severity, CVSS 4.3. EPSS: 22.4% chance of exploitation in the next 30 days.

The mod_proxy_ajp module in the Apache HTTP Server before 2.2.21, when used with mod_proxy_balancer in certain configurations, allows remote attackers to cause a denial of service (temporary "error state" in the backend server) via a malformed HTTP request.

Affected products

• Apache HTTP Server: from 2.2.12, up to and including 2.2.20
• Red Hat JBoss Enterprise Web Server: version 1.0.0 only

Published 2011-09-20. Last modified 2026-06-16.