CVE-2011-3607: Apache HTTP Server

Medium severity, CVSS 4.4. EPSS: 4.7% chance of exploitation in the next 30 days.

Integer overflow in the ap_pregsub function in server/util.c in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x through 2.2.21, when the mod_setenvif module is enabled, allows local users to gain privileges via a .htaccess file with a crafted SetEnvIf directive, in conjunction with a crafted HTTP request header, leading to a heap-based buffer overflow.

Affected products

• Apache HTTP Server: version 2.0 only; version 2.0.9 only; version 2.0.28 only; version 2.0.32 only; version 2.0.34 only; version 2.0.35 only; …

Published 2011-11-08. Last modified 2026-06-16.