CVE-2026-53435 Jenkins arbitrary type deserialization from attacker-controlled config.xml allows remote code execution and user impersonation
Attackers can deserialize arbitrary types via config.xml to impersonate users, execute code, or read files on the Jenkins controller.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53435?
CVE-2026-53435 is a high-severity unsafe deserialization vulnerability in Jenkins Jenkins, published on 10 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-502
Which versions are affected by CVE-2026-53435?
5 open source packages ship an affected version, including org.jenkins-ci.main:jenkins-core and jenkins. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.jenkins-ci.main:jenkins-core Maven | All versions | 2.555.3 |
org.jenkins-ci.main:jenkins-core Maven | All versions | 2.555.3 |
org.jenkins-ci.main:jenkins-core Maven | From 2.556 | 2.568 |
org.jenkins-ci.main:jenkins-core Maven | From 2.556 | 2.568 |
jenkins Bitnami | All versions | 2.555.3, 2.568.0 |
Products include Jenkins Jenkins.
How do I fix CVE-2026-53435?
Upgrade org.jenkins-ci.main:jenkins-core to a fixed version for your release line: 2.555.3 or 2.568.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-53435 being exploited?
There is no known exploitation of CVE-2026-53435 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Jenkins Jenkins
- CVE-2024-23897 Jenkins Command Line Interface (CLI) Path Traversal
- CVE-2018-1000861 Jenkins Stapler Web Framework Deserialization of Untrusted Data
- CVE-2017-1000353 Jenkins Remote Code Execution
- CVE-2015-5317 Jenkins User Interface (UI) Information Disclosure
- CVE-2021-21690 Multiple vulnerabilities allow bypassing path filtering of agent-to-controller access control in Jenkins
Sources
Also known as BIT-jenkins-2026-53435, GHSA-g2xq-2v27-4rh3, MINI-5wfq-87mx-3vqx, MINI-6hj5-wf3w-47pw, MINI-jwg4-534j-7jj6, MINI-mjqf-9cjc-73hq and 3 more.