CVE-2026-84655

Medium

Description

Jenkins 2.579 and earlier, LTS 2.568.2 and earlier does not escape map keys when serializing objects as JSON and Python through its REST API, allowing attackers able to control map property names to inject arbitrary fields into JSON and Python API responses.

SeverityMedium

CVSS4.3

Exploit probability—

Product

Jenkins

PublishedSep 2, 2026

First seenSep 2, 2026

Weakness typeCWE-116CWE-116

How to fix

Vendor advisories

jenkins.io/security/advisory/2026-09-02/#SECURITY-3879

Affected products

Product	Affected versions	Fixed in
jenkins jenkins	v ≤ 2.568.2, v ≤ 2.579	—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.