CVE-2011-4858: Apache Tomcat

Medium severity, CVSS 5.0. EPSS: 79.7% chance of exploitation in the next 30 days.

Apache Tomcat before 5.5.35, 6.x before 6.0.35, and 7.x before 7.0.23 computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters.

Affected products

• Apache Tomcat: version 5.5.35 only; version 6.0.0 only; version 6.0.1 only; version 6.0.2 only; version 6.0.3 only; version 6.0.4 only; …

Published 2012-01-05. Last modified 2026-06-16.