When the default servlet in Apache Tomcat versions 9.0.0.M1 to 9.0.11, 8.5.0 to 8.5.33 and 7.0.23 to 7.0.90 returned a redirect to a directory (e.g. redirecting to ‘/foo/’ when the user requested ‘/foo’) a specially crafted URL could be used to cause the redirect to be generated to any URI of the attackers choice.
bugzilla.redhat.com/show_bug.cgi?id=1636512
www.cve.org/CVERecord?id=CVE-2018-11784 https://nvd.nist.gov/vuln/detail/CVE-2018-11784 tomcat.apache.org/security-7.html#Fixed_in_Apache_Tomcat_7.0.91 http://tomcat.apache.org/security-8.html#Fixed_in_Apache_Tomcat_8.5.34 http://tomcat.apache.org/security-9.html#Fixed_in_Apache_Tomcat_9.0.12