CVE-2021-21652
📋 TL;DR
This CSRF vulnerability in Jenkins Xray plugin allows attackers to trick authenticated users into unknowingly connecting Jenkins to attacker-controlled URLs using stolen credential IDs. This could expose sensitive credentials stored in Jenkins. Affects Jenkins administrators using Xray Test Management for Jira plugin version 2.4.0 or earlier.
💻 Affected Systems
- Jenkins Xray - Test Management for Jira Plugin
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers capture all credentials stored in Jenkins, potentially gaining access to integrated systems like databases, cloud services, and internal infrastructure.
Likely Case
Attackers capture specific credentials used by the Xray plugin, compromising Jira integration and potentially other systems using those credentials.
If Mitigated
With proper CSRF protections and credential management, impact is limited to failed connection attempts to attacker URLs.
🎯 Exploit Status
Requires attacker to obtain credential IDs through other means and trick authenticated admin into visiting malicious page.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.4.1
Vendor Advisory: https://www.jenkins.io/security/advisory/2021-05-11/#SECURITY-2251%20%281%29
Restart Required: Yes
Instructions:
1. Update Jenkins Xray plugin to version 2.4.1 or later via Jenkins Plugin Manager. 2. Restart Jenkins service. 3. Verify plugin version in Installed Plugins list.
🔧 Temporary Workarounds
Enable CSRF Protection
allEnsure Jenkins CSRF protection is enabled globally
Check 'Prevent Cross Site Request Forgery exploits' is enabled in Jenkins > Configure Global Security
Restrict Admin Access
allLimit administrative access to trusted users only
Configure role-based access control in Jenkins > Configure Global Security
🧯 If You Can't Patch
- Disable or uninstall Xray plugin if not essential
- Implement network segmentation to isolate Jenkins from sensitive systems
🔍 How to Verify
Check if Vulnerable:
Check installed plugin version in Jenkins > Manage Jenkins > Manage Plugins > Installed tabCheck Version:
Check Jenkins web interface or plugin manifest fileVerify Fix Applied:
Verify Xray plugin version is 2.4.1 or higher in Installed Plugins list📡 Detection & Monitoring
Log Indicators:
- Unexpected connection attempts to external URLs in Jenkins logs
- Failed authentication attempts from Xray plugin
Network Indicators:
- Outbound connections from Jenkins to unfamiliar domains on port 443
SIEM Query:
source="jenkins.log" AND ("Xray" OR "test.management") AND ("connection" OR "credential")