The drools serialization format allows to embed class files. Upon deserialization those are loaded by the VM that runs the drools engine. If that (attacker-controlled) class files defines code in a static initializer it is executed during deserialization.
An improper input sanitization flaw was found in the way JBoss Seam web application framework processed certain parametrized JBoss Expression Language expressions. A remote attacker could use this flaw to execute arbitrary code via a URL, containing appended, specially-crafted expression language parameters, provided to certain applications based on the JBoss Seam framework. Note: A properly configured and enabled Java Security Manager would prevent exploitation of this flaw.
References: [1] http://seamframework.org/ [2] http://docs.jboss.org/seam/2.2.0.GA/en-US/html/elenhancements.html
Acknowledgements:
Red Hat would like to thank Meder Kydyraliev of Google Security Team for responsibly reporting this issue.
The Web Console (aka web-console) in JBossAs in Red Hat JBoss Enterprise Application Platform (aka JBoss EAP or JBEAP) 4.2 before 4.2.0.CP09 and 4.3 before 4.3.0.CP08 performs access control only for the GET and POST methods, which allows remote attackers to obtain sensitive information via an unspecified request that uses a different method.