CVE-2016-6816: Apache Tomcat

High severity, CVSS 7.1. EPSS: 39.6% chance of exploitation in the next 30 days.

The code in Apache Tomcat 9.0.0.M1 to 9.0.0.M11, 8.5.0 to 8.5.6, 8.0.0.RC1 to 8.0.38, 7.0.0 to 7.0.72, and 6.0.0 to 6.0.47 that parsed the HTTP request line permitted invalid characters. This could be exploited, in conjunction with a proxy that also permitted the invalid characters but with a different interpretation, to inject data into the HTTP response. By manipulating the HTTP response the attacker could poison a web-cache, perform an XSS attack and/or obtain sensitive information from requests other then their own.

Affected products

• Apache Tomcat: 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; version 6.0.5 only; …

Published 2017-03-20. Last modified 2026-06-17.