CVE-2025-53652: Jenkins Git Parameter RCE Vulnerability

CVE-2025-53652 Overview

Jenkins Git Parameter Plugin version 439.vb_0e46ca_14534 and earlier contains an improper input validation vulnerability that fails to validate Git parameter values submitted during builds. This flaw allows attackers with Item/Build permission to inject arbitrary values into Git parameters, bypassing the expected constraints of offered choices. The vulnerability stems from missing validation logic that should ensure user-submitted parameter values match one of the predefined options.

Critical Impact

Attackers with Item/Build permissions can inject arbitrary values into Git parameters, potentially leading to unauthorized access to repositories, data exfiltration, or manipulation of CI/CD pipelines.

Affected Products

• Jenkins Git Parameter Plugin version 439.vb_0e46ca_14534 and earlier
• Jenkins installations utilizing the Git Parameter Plugin for build parameterization

Discovery Timeline

• 2025-07-09 - CVE-2025-53652 published to NVD
• 2025-07-09 - Jenkins releases security advisory #SECURITY-3419
• 2025-11-04 - Last updated in NVD database

Technical Details for CVE-2025-53652

Vulnerability Analysis

This vulnerability is classified as CWE-20 (Improper Input Validation). The Jenkins Git Parameter Plugin provides functionality to parameterize builds with Git-related values such as branch names, tags, or revisions. Under normal operation, administrators configure a set of allowed choices that users can select when triggering builds.

The flaw exists because the plugin does not properly validate that the submitted Git parameter value actually matches one of the configured choices. When a user with Item/Build permission initiates a build, they can manipulate the request to include arbitrary values for Git parameters, rather than being limited to the predefined options presented in the UI.

This validation gap allows attackers to specify malicious Git references, potentially enabling unauthorized repository access, injection of untrusted code into build processes, or manipulation of downstream deployment pipelines.

Root Cause

The root cause is the absence of server-side validation logic in the Git Parameter Plugin. While the plugin may present a restricted set of choices in the user interface, it fails to enforce these restrictions when processing the submitted build request. This is a classic case of client-side validation without corresponding server-side enforcement, allowing attackers to bypass UI-level controls by crafting direct HTTP requests.

Attack Vector

The attack is network-based and requires the attacker to have Item/Build permissions within the Jenkins instance. The attacker can exploit this vulnerability by:

1. Identifying a Jenkins job that uses the Git Parameter Plugin
2. Crafting a build request with a manipulated Git parameter value that differs from the allowed choices
3. Submitting the request directly to the Jenkins API or modifying form data before submission
4. The plugin accepts the arbitrary value without validation, incorporating it into the build process

The vulnerability allows parameter injection through the build trigger mechanism, where an attacker substitutes legitimate Git references with attacker-controlled values that can reference arbitrary branches, tags, or even external repositories depending on the job configuration.

Detection Methods for CVE-2025-53652

Indicators of Compromise

• Unexpected or unrecognized Git parameter values in Jenkins build logs
• Build requests containing Git references that do not match configured choices
• Unusual repository checkout activity or access to unexpected branches/tags
• API requests to build endpoints with modified parameter payloads

Detection Strategies

• Review Jenkins audit logs for build requests containing parameter values outside the configured choices
• Implement monitoring on Jenkins API endpoints that handle build submissions
• Analyze build history for jobs using Git Parameter Plugin for anomalous Git reference patterns
• Enable detailed logging for Git operations to identify unexpected repository interactions

Monitoring Recommendations

• Configure alerting for builds triggered with non-standard Git parameter values
• Monitor network traffic to Jenkins for suspicious build request patterns
• Implement log aggregation and analysis for Jenkins controller and agent nodes
• Establish baseline metrics for normal Git parameter usage and alert on deviations

How to Mitigate CVE-2025-53652

Immediate Actions Required

• Update the Jenkins Git Parameter Plugin to the latest patched version immediately
• Review and restrict Item/Build permissions to trusted users only
• Audit recent builds for potential exploitation attempts with unexpected Git parameter values
• Consider temporarily disabling the Git Parameter Plugin until patching is complete

Patch Information

Jenkins has released a security update addressing this vulnerability. Refer to the Jenkins Security Advisory #SECURITY-3419 for complete details on the patch and updated plugin version. Organizations should update the Git Parameter Plugin through the Jenkins Plugin Manager to obtain the fix.

Additional technical discussion is available on the Openwall OSS-Security mailing list.

Workarounds

• Restrict Item/Build permissions to only highly trusted users until patching is possible
• Implement additional access controls at the repository level to limit impact of parameter injection
• Use Jenkins Pipeline scripts with hardcoded Git references instead of parameterized values where feasible
• Deploy network-level controls to limit access to Jenkins build trigger endpoints