Jenkins Jenkins
CVE-2026-84648
In Jenkins 2.579 and earlier, LTS 2.568.2 and earlier, the system log viewer does not escape log record metadata (source, level, and timestamp) resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers in control of agent processes.
What this means for your business
- It affects Jenkins. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.6% chance of attack attempts being seen in the next 30 days, ranking above 45% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Jenkins, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Fastnexa security experts
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Scoring
- CVSS
- 8.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- Weakness
- CWE-79
- Assigned by
- jenkinsci-cert@googlegroups.com
Dates
- Published
- 2026-09-02
- Last modified
- 2026-09-11
- Sources
- NVD
Affected products
- Jenkins Jenkins- 2.568.3, - 2.580
As listed in the NVD configuration data. Not a statement about your estate.