Apache · Apache Tomcat · CVE-2016-6816
**Name of the Vulnerable Software and Affected Versions**
Apache Tomcat versions 9.0.0.M1 through 9.0.0.M11
Apache Tomcat versions 8.5.0 through 8.5.6
Apache Tomcat versions 8.0.0.RC1 through 8.0.38
Apache Tomcat versions 7.0.0 through 7.0.72
Apache Tomcat versions 6.0.0 through 6.0.47
**Description**
The code in Apache Tomcat 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 than their own.
**Recommendations**
For Apache Tomcat versions 9.0.0.M1 through 9.0.0.M11, update to a version outside of this range to resolve the issue.
For Apache Tomcat versions 8.5.0 through 8.5.6, update to a version outside of this range to resolve the issue.
For Apache Tomcat versions 8.0.0.RC1 through 8.0.38, update to a version outside of this range to resolve the issue.
For Apache Tomcat versions 7.0.0 through 7.0.72, update to a version outside of this range to resolve the issue.
For Apache Tomcat versions 6.0.0 through 6.0.47, update to a version outside of this range to resolve the issue.
As a temporary workaround, consider restricting access to the HTTP request line parsing functionality until a patch is available.