CVE-2012-0021: Apache HTTP Server

Low severity, CVSS 2.6. EPSS: 30.3% chance of exploitation in the next 30 days.

The log_cookie function in mod_log_config.c in the mod_log_config module in the Apache HTTP Server 2.2.17 through 2.2.21, when a threaded MPM is used, does not properly handle a %{}C format string, which allows remote attackers to cause a denial of service (daemon crash) via a cookie that lacks both a name and a value.

Affected products

• Apache HTTP Server: version 2.2.17 only; version 2.2.18 only; version 2.2.19 only; version 2.2.20 only; version 2.2.21 only

Published 2012-01-28. Last modified 2026-06-16.