Description
Jenkins 2.587 and earlier, LTS 2.580.1 and earlier does not restrict item types in collections after deserialization, allowing attackers with access to POST config.xml API endpoints to submit crafted `config.xml` files that can lead to, e.g., stored cross-site scripting (XSS) vulnerabilities.
Affected products
jenkins: jenkins
References1
- www.jenkins.io/security/advisory/2026-10-28/#SECURITY-4225 MitigationVendor Advisory
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 22 · as of 3 November 2026
- CWE
- CWE-502
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