CVE-2024-39459
📋 TL;DR
The Jenkins Plain Credentials Plugin versions 182.v468b_97b_9dcb_8 and earlier store secret file credentials unencrypted (only Base64 encoded) on the Jenkins controller file system. This allows users with file system access or Item/Extended Read permission to view these credentials. Organizations using affected plugin versions with secret file credentials are impacted.
💻 Affected Systems
- Jenkins Plain Credentials Plugin
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers with file system access or Item/Extended Read permission could exfiltrate all stored secret file credentials, leading to credential theft and potential lateral movement.
Likely Case
Insiders or compromised accounts with appropriate permissions could access and misuse stored credentials for unauthorized actions.
If Mitigated
With strict access controls and monitoring, impact is limited to authorized users who already have elevated permissions.
🎯 Exploit Status
Exploitation requires existing access to Jenkins controller file system or Item/Extended Read permission.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 183.v7b_36b_2a_70c or later
Vendor Advisory: https://www.jenkins.io/security/advisory/2024-06-26/#SECURITY-2495
Restart Required: Yes
Instructions:
1. Update Jenkins Plain Credentials Plugin to version 183.v7b_36b_2a_70c or later via Jenkins Plugin Manager. 2. Restart Jenkins controller. 3. Verify plugin version in Installed Plugins list.
🔧 Temporary Workarounds
Restrict File System Access
allLimit access to Jenkins controller file system to only necessary administrators.
Use OS-level permissions (chmod/chown on Linux, ACLs on Windows) to restrict access to Jenkins home directory
Review and Limit Permissions
allAudit and reduce Item/Extended Read permissions to minimum necessary users.
Review Jenkins Role-Based Authorization Strategy or Matrix Authorization Strategy configurations
🧯 If You Can't Patch
- Migrate secret file credentials to other credential types that are properly encrypted
- Implement strict monitoring and auditing of file system access and credential usage
🔍 How to Verify
Check if Vulnerable:
Check Jenkins Plugin Manager for Plain Credentials Plugin version. If version is 182.v468b_97b_9dcb_8 or earlier, system is vulnerable.Check Version:
On Jenkins web interface: Manage Jenkins > Manage Plugins > Installed tab, search for 'Plain Credentials'Verify Fix Applied:
Verify Plain Credentials Plugin version is 183.v7b_36b_2a_70c or later in Jenkins Plugin Manager.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to Jenkins controller file system
- Unusual credential usage patterns
Network Indicators:
- Unusual outbound connections following file system access
SIEM Query:
source="jenkins" AND (event="File access" OR event="Permission change") AND user NOT IN ["authorized_users"]