A flaw was found in the way JBoss RichFaces handled deserialization. A remote attacker could use this flaw to trigger the execution of the deserialization methods in any serializable class deployed on the server. This could lead to a variety of security impacts depending on the deserialization logic of these classes.

It was reported [1] that remote attackers can inject EL (Expression Language) via "do" parameter. This leads to remote Java method execution vulnerability.

[1]: https://issues.jboss.org/browse/RF-13977

JBoss RichFaces 3.1.0 through 3.3.4 allows unauthenticated remote attackers to inject expression language (EL) expressions and execute arbitrary Java code via a /DATA/ substring in a path with an org.richfaces.renderkit.html.Paint2DResource$ImageData object, aka RF-14310.

JBoss RichFaces 4.5.3 through 4.5.17 allows unauthenticated remote attackers to inject an arbitrary expression language (EL) variable mapper and execute arbitrary Java code via a MediaOutputResource's resource request, aka RF-14309.