Description
Jenkins 2.579 and earlier, LTS 2.568.2 and earlier does not escape map keys when serializing objects as JSON and Python through its REST API, allowing attackers able to control map property names to inject arbitrary fields into JSON and Python API responses.
Affected products
jenkins: jenkins
References1
- www.jenkins.io/security/advisory/2026-09-02/#SECURITY-3879 Vendor Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 41 · as of 2 November 2026
- CWE
- CWE-116
Could this be exploited in your environment?
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