SB2019012212 - Sandbox restrictions bypass in Pipeline: Groovy plugin for Jenkins

Description

This security bulletin contains information about 1 vulnerability.

1) Improper access control (CVE-ID: CVE-2019-1003001)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber

The vulnerability allows a remote attacker to bypass sandbox restrictions.

The vulnerability exists due to improper access restrictions in "src/main/java/org/jenkinsci/plugins/workflow/cps/CpsFlowDefinition.java" and "src/main/java/org/jenkinsci/plugins/workflow/cps/CpsGroovyShellFactory.java" when applying AST transforming annotations such as @Grab to source code elements. A remote authenticated attacker with Overall/Read permission, or able to control Jenkins file or sandboxed Pipeline shared library contents in SCM, can bypass the sandbox protection and execute arbitrary code on the Jenkins master.

Remediation

Install update from vendor's website.

References

• http://packetstormsecurity.com/files/152132/Jenkins-ACL-Bypass-Metaprogramming-Remote-Code-Execution.html
• https://jenkins.io/security/advisory/2019-01-08/#SECURITY-1266