Red Hat Security Advisory 2017-0527-01 – Apache Tomcat is a servlet container for the Java Servlet and JavaServer Pages technologies. Security Fix: It was discovered that the code 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, or obtain sensitive information from requests other then their own.