CVE-2026-84649: Jenkins Project Jenkins

High severity, CVSS 8.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In Stapler 1839.ved17667b_a_eb_5 through 2107.v8dfcb_e8ed317 (both inclusive), except 2088.2093.vd7c3e58008a_6, included in Jenkins 2.447 through 2.579 (both inclusive), LTS 2.452.1 through 2.568.2 (both inclusive), an HTTP endpoint serving dynamically generated JavaScript resources embeds the user's cross-site request forgery (CSRF) token (crumb) as a string literal, allowing attackers with control over a page hosted on the same site as Jenkins to obtain a valid crumb for the targeted user's session and perform actions on their behalf.

Affected products

• Jenkins Project Jenkins: from 2.447, before 2.568.3 (fixed in 2.568.3); from 2.569, before 2.580 (fixed in 2.580)

Published 2026-09-02. Last modified 2026-09-03.