module

Jenkins ACL Bypass and Metaprogramming RCE

Disclosed
Jan 8, 2019
Created
Mar 19, 2019

Description

This module exploits a vulnerability in Jenkins dynamic routing to
bypass the Overall/Read ACL and leverage Groovy metaprogramming to
download and execute a malicious JAR file.

When the "Java Dropper" target is selected, the original entry point
based on classLoader.parseClass is used, which requires the use of
Groovy metaprogramming to achieve RCE.

When the "Unix In-Memory" target is selected, a newer, higher-level,
and more universal entry point based on GroovyShell.parse is used.
This permits the use of in-memory arbitrary command execution.

The ACL bypass gadget is specific to Jenkins on later versions of Jenkins.

Tested against Jenkins 2.137 and Pipeline: Groovy Plugin 2.61.

Authors

Orange Tsai
Mikhail Egorov
George Noseevich
wvu [email protected]

Platform

Java,Unix

Architectures

cmd, java

Module Options

To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':


msf > use exploit/multi/http/jenkins_metaprogramming
msf exploit(jenkins_metaprogramming) > show targets
...targets...
msf exploit(jenkins_metaprogramming) > set TARGET < target-id >
msf exploit(jenkins_metaprogramming) > show options
...show and set options...
msf exploit(jenkins_metaprogramming) > exploit

Title
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