CVE-2026-53440 Jenkins: Open Redirect phishing attacks possible via "from" parameter in "Delegate to servlet container"

What is CVE-2026-53440?

CVE-2026-53440 is a medium-severity vulnerability in Jenkins Jenkins, published on 10 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Jenkins 2.567 and earlier, LTS 2.555.2 and earlier does not ensure that the "from" parameter in the "Delegate to servlet container" security realm is safe to redirect to after login, allowing attackers to perform phishing attacks by redirecting users to an attacker-controlled domain.

Weakness: CWE-601

Which versions are affected by CVE-2026-53440?

5 open source packages ship an affected version, including org.jenkins-ci.main:jenkins-core and jenkins. It affects 1 product.

Products include Jenkins Jenkins.

How do I fix CVE-2026-53440?

Upgrade org.jenkins-ci.main:jenkins-core to a fixed version for your release line: 2.555.3 or 2.568.

Is CVE-2026-53440 being exploited?

There is no known exploitation of CVE-2026-53440 in the wild and no public exploit code.

Other vulnerabilities in Jenkins Jenkins

• CVE-2024-23897 Jenkins Command Line Interface (CLI) Path Traversal Exploited Critical 9.8
• CVE-2018-1000861 Jenkins Stapler Web Framework Deserialization of Untrusted Data Exploited Critical 9.8
• CVE-2017-1000353 Jenkins Remote Code Execution Exploited Critical 9.8
• CVE-2015-5317 Jenkins User Interface (UI) Information Disclosure Exploited High 7.5
• CVE-2021-21690 Multiple vulnerabilities allow bypassing path filtering of agent-to-controller access control in Jenkins Critical 9.8

All Jenkins Jenkins vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-jenkins-2026-53440, GHSA-92m7-4fpw-2wxm, MINI-54wg-42hp-2r68, MINI-86fc-pgm3-f88w, MINI-c4wv-99vp-52qf, MINI-cq6g-3f47-q9p7 and 3 more.