CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Called exploited 5 days after disclosure.
Measured from the CVE publication date to the earliest of 1 KEV catalogue that list it.
The life of this vulnerability
- CVE published
- First KEV listing5d
- Last sightingsame day
Gaps are compressed to equal steps. The elapsed time is printed under each.
Which catalogues call it exploited
- CISA KEVUS federaldoes not list it
- EUVDENISA, European Uniondoes not list it
- VulnCheck KEVcommercial researchlisted Jun 15, 2026
- CIRCLaggregator, mirrors the abovelisted Jun 15, 2026, not counted
This rests on a single catalogue. No second catalogue corroborates the claim that it is being exploited. CIRCL is an aggregator and is not counted.
Public exploitation evidence
- reported exploitationx.com/DefusedCyber/status/2066446206285291526
1 public report collected from VulnCheck and CIRCL, first on Jun 15, 2026. Each links to its original source. We have not verified them.
Description
In Jenkins 2.567 and earlier, LTS 2.555.2 and earlier, it is possible for attackers to have Jenkins deserialize arbitrary types defined in Jenkins core or plugins from an attacker-controlled `config.xml` submission in a way that allows them to handle HTTP requests afterwards. This can be used to impersonate any user and send HTTP requests on their behalf, up to and including use of the Script Console to run arbitrary code, or to read arbitrary files from the Jenkins controller.