XSS in Jenkins Project Update-Center2

CVE-2026-84677

Jenkins update-center2 3.18.3 and earlier does not escape plugin-provided values (plugin names, descriptions, and version metadata) on plugin download index pages, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers able to provide a plugin for hosting.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (12.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-84677: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-84677?
CVE-2026-84677 is a medium-severity vulnerability in Jenkins Project Update-Center2, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-09-02.
How severe is CVE-2026-84677?
Medium severity. CVSS v3 base score is 5.4 out of 10.