CVE-2025-23989
📋 TL;DR
This CSRF vulnerability in the WordPress Internal Link Builder plugin allows attackers to trick authenticated administrators into performing unintended actions. Attackers can exploit this to inject malicious scripts that execute when other users visit affected pages, potentially leading to stored XSS. All WordPress sites using Internal Link Builder version 1.0 or earlier are affected.
💻 Affected Systems
- WordPress Internal Link Builder plugin
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Attackers could inject persistent malicious scripts that steal admin credentials, deface websites, or redirect users to malicious sites when any user visits compromised pages.
Likely Case
Attackers create malicious links that trick administrators into unknowingly adding malicious scripts to website content, leading to client-side attacks against visitors.
If Mitigated
With proper CSRF protections and content security policies, the attack surface is reduced, though the vulnerability still exists in the plugin code.
🎯 Exploit Status
Exploitation requires social engineering to trick authenticated admin users into clicking malicious links while logged in.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check WordPress plugin repository for updated version
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins > Installed Plugins. 3. Find Internal Link Builder. 4. Click 'Update Now' if available. 5. If no update available, deactivate and delete the plugin.
🔧 Temporary Workarounds
Implement CSRF Protection
WordPressAdd nonce verification to plugin forms and AJAX requests
Requires code modification: Add wp_nonce_field() to forms and check_admin_referer() or wp_verify_nonce() in processing
🧯 If You Can't Patch
- Deactivate and remove the Internal Link Builder plugin immediately
- Implement Content Security Policy headers to restrict script execution sources
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin > Plugins > Installed Plugins for Internal Link Builder version 1.0 or earlierCheck Version:
wp plugin list --name=internal-link-builder --field=versionVerify Fix Applied:
Verify plugin is either updated to patched version or completely removed from plugins directory📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to wp-admin/admin-ajax.php or wp-admin/admin-post.php with plugin-specific actions
- Multiple failed nonce verification attempts
Network Indicators:
- Suspicious referer headers in admin requests
- Unexpected cross-origin requests to admin endpoints
SIEM Query:
source="wordpress" AND (uri_path="/wp-admin/admin-ajax.php" OR uri_path="/wp-admin/admin-post.php") AND (query_string CONTAINS "internal_link_builder" OR query_string CONTAINS "sablab")