Controller code execution via writable shared libraries
Published Nov 4, 2021 · Updated Aug 3, 2024
Access control failure in Jenkins 2.318 and earlier and LTS 2.303.2 and earlier allows attackers to execute code on the controller. FilePath APIs fail to block agent read and write access to build-directory libs/ content, letting a modified trusted shared library run unsandboxed in the controller process. Exploitation requires control of an agent process and can replace library code that a Pipeline later loads.
Summary
What happened
Access control failure in Jenkins 2.318 and earlier and LTS 2.303.2 and earlier allows attackers to execute code on the controller. FilePath APIs fail to block agent read and write access to build-directory libs/ content, letting a modified trusted shared library run unsandboxed in the controller process. Exploitation requires control of an agent process and can replace library code that a Pipeline later loads.
The record
- CVE
- CVE-2021-21696
- Published
- Nov 4, 2021
- Updated
- Aug 3, 2024
- Vendor
- Jenkins Project
- Product
- Jenkins
- Classifications
- T1059
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Nov 4, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=unspecified <=2.318
- Affected versionversion=unspecified <=LTS 2.303.2
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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