Amazon Linux AMI Security Advisory: ALAS-2015-527
Advisory Release Date: 2015-05-14 23:52 Pacific
It was discovered that JBoss Web / Apache Tomcat did not limit the length of chunk sizes when using chunked transfer encoding. A remote attacker could use this flaw to perform a denial of service attack against JBoss Web / Apache Tomcat by streaming an unlimited quantity of data, leading to excessive consumption of server resources. (CVE-2014-0075 )
It was found that the org.apache.catalina.servlets.DefaultServlet implementation in JBoss Web / Apache Tomcat allowed the definition of XML External Entities (XXEs) in provided XSLTs. A malicious application could use this to circumvent intended security restrictions to disclose sensitive information. (CVE-2014-0096 )
It was found that JBoss Web / Apache Tomcat did not check for overflowing values when parsing request content length headers. A remote attacker could use this flaw to perform an HTTP request smuggling attack on a JBoss Web / Apache Tomcat server located behind a reverse proxy that processed the content length header correctly. (CVE-2014-0099 )
It was discovered that the ChunkedInputFilter in Tomcat did not fail subsequent attempts to read input after malformed chunked encoding was detected. A remote attacker could possibly use this flaw to make Tomcat process part of the request body as new request, or cause a denial of service. (CVE-2014-0227 )
Run yum update tomcat8 to update your system.