Jenkins Jenkins
CVE-2026-84652
In Jenkins 2.579 and earlier, LTS 2.568.2 and earlier, Jenkins does not rotate the session when a user is authenticated via the "remember me" cookie, allowing attackers able to serve content on the same site as Jenkins to set a known session cookie in the victim's browser, which after the victim authenticates via the "remember me" cookie, grants the attacker access to Jenkins as that user.
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, with an ordinary user login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.5% chance of attack attempts being seen in the next 30 days, ranking above 39% 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
Not sure if your company is exposed to CVE-2026-84652?
Tell us where you run Jenkins Jenkins and a Fastnexa penetration tester will check whether this flaw, or others like it, can be used against your websites, apps and network.
The full test is free for our first 10 founding clients until 31 December 2026. See the offer
Think you’ve already been hit? Don’t wait on a form: call or WhatsApp +1 (732) 454 2616. We reply within 1 hour, 24/7. Emergency help →
Scoring
- CVSS
- 7.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N- Weakness
- CWE-384
- 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.