Updated jbossweb packages that fix multiple security issues are now available for JBoss Enterprise Application Platform 5.1.2 for Red Hat Enterprise Linux 4, 5, and 6. The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.
JBoss Web is the web container, based on Apache Tomcat, in JBoss Enterprise Application Platform. It provides a single deployment platform for the JavaServer Pages (JSP) and Java Servlet technologies. A flaw was found in the way JBoss Web handled UTF-8 surrogate pair characters. If JBoss Web was hosting an application with UTF-8 character encoding enabled, or that included user-supplied UTF-8 strings in a response, a remote attacker could use this flaw to cause a denial of service (infinite loop) on the JBoss Web server. (CVE-2011-4610) It was found that the Java hashCode() method implementation was susceptible to predictable hash collisions. A remote attacker could use this flaw to cause JBoss Web to use an excessive amount of CPU time by sending an HTTP request with a large number of parameters whose names map to the same hash value. This update introduces a limit on the number of parameters and headers processed per request to mitigate this issue. The default limit is 512 for parameters and 128 for headers. These defaults can be changed by setting the org.apache.tomcat.util.http.Parameters.MAX_COUNT and org.apache.tomcat.util.http.MimeHeaders.MAX_COUNT system properties in "jboss-as/server/[PROFILE]/deploy/properties-service.xml". (CVE-2011-4858) It was found that JBoss Web did not handle large numbers of parameters and large parameter values efficiently. A remote attacker could make a JBoss Web server use an excessive amount of CPU time by sending an HTTP request containing a large number of parameters or large parameter values. This update introduces limits on the number of parameters and headers processed per request to address this issue. Refer to the CVE-2011-4858 description for information about the org.apache.tomcat.util.http.Parameters.MAX_COUNT and org.apache.tomcat.util.http.MimeHeaders.MAX_COUNT system properties. (CVE-2012-0022) Multiple flaws were found in the way JBoss Web handled HTTP DIGEST authentication. These flaws weakened the JBoss Web HTTP DIGEST authentication implementation, subjecting it to some of the weaknesses of HTTP BASIC authentication, for example, allowing remote attackers to perform session replay attacks. (CVE-2011-1184, CVE-2011-5062, CVE-2011-5063, CVE-2011-5064) A flaw was found in the way JBoss Web handled sendfile request attributes when using the HTTP APR (Apache Portable Runtime) or NIO (Non-Blocking I/O) connector. A malicious web application running on a JBoss Web instance could use this flaw to bypass security manager restrictions and gain access to files it would otherwise be unable to access, or possibly terminate the Java Virtual Machine (JVM). (CVE-2011-2526) Red Hat would like to thank NTT OSSC for reporting CVE-2011-4610; oCERT for reporting CVE-2011-4858; and the Apache Tomcat project for reporting CVE-2011-2526. oCERT acknowledges Julian Walde and Alexander Klink as the original reporters of CVE-2011-4858. Warning: Before applying this update, back up your JBoss Enterprise Application Platform's "jboss-as/server/[PROFILE]/deploy/" directory, along with all other customized configuration files. Users of JBoss Enterprise Application Platform 5.1.2 on Red Hat Enterprise Linux 4, 5, and 6 should upgrade to these updated packages, which correct these issues. The JBoss server process must be restarted for this update to take effect.