Jenkins < 1.642.2 / 1.650 Java Object Deserialization RCE
Critical Nessus Plugin ID 89725
SynopsisThe remote web server is affected by a remote code execution vulnerability.
DescriptionThe remote web server hosts a version of Jenkins or Jenkins Enterprise that is prior to 1.642.2 or 1.650. It is, therefore, affected by a Java deserialization vulnerability. An unauthenticated, remote attacker can exploit this, by deserializing specific java.rmi and sun.rmi objects, to start a JRMP listener on the server. The JRMP listener can then be exploited over RMI using objects in the Groovy or Apache Commons Collections libraries, resulting in the execution of arbitrary code.
Note that the server is reportedly affected by a number of other vulnerabilities per the Jenkins Security advisory; however, Nessus has not tested for these.
SolutionUpgrade to Jenkins version 1.642.2 / 1.650 or later. Alternatively, disable the CLI port per the vendor advisory.