CVE-2025-4054
📋 TL;DR
The Relevanssi WordPress plugin has a stored XSS vulnerability in its highlights functionality that allows unauthenticated attackers to inject malicious scripts into search result pages. When users view compromised search results, the scripts execute in their browsers. All WordPress sites using Relevanssi versions up to 4.24.3 are affected.
💻 Affected Systems
- Relevanssi – A Better Search WordPress 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 steal admin session cookies, redirect users to malicious sites, deface websites, or perform actions as authenticated users.
Likely Case
Attackers inject malicious scripts that steal user session data or redirect users to phishing sites via search results.
If Mitigated
With proper input validation and output escaping, the vulnerability is prevented and no impact occurs.
🎯 Exploit Status
The vulnerability is in publicly accessible search functionality and requires minimal technical skill to exploit.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.24.4 or later
Vendor Advisory: https://plugins.trac.wordpress.org/changeset/3283795/
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find Relevanssi and click 'Update Now'. 4. Verify version is 4.24.4 or higher.
🔧 Temporary Workarounds
Disable highlights functionality
allTemporarily disable the vulnerable highlights feature in Relevanssi settings
Disable plugin
allDeactivate Relevanssi plugin until patched
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block XSS payloads in search parameters
- Restrict search functionality to authenticated users only
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel → Plugins → Installed Plugins → Relevanssi versionCheck Version:
wp plugin list --name=relevanssi --field=versionVerify Fix Applied:
Verify Relevanssi version is 4.24.4 or higher in WordPress admin📡 Detection & Monitoring
Log Indicators:
- Unusual search queries containing script tags or JavaScript code
- Multiple failed search attempts with suspicious patterns
Network Indicators:
- HTTP requests to search endpoints with encoded script payloads
SIEM Query:
source="wordpress.log" AND ("relevanssi" OR "search") AND ("<script>" OR "javascript:" OR "onerror=" OR "onload=")🔗 References
- https://plugins.trac.wordpress.org/browser/relevanssi/tags/4.24.3/lib/excerpts-highlights.php#L508
- https://plugins.trac.wordpress.org/browser/relevanssi/tags/4.24.3/lib/excerpts-highlights.php#L683
- https://plugins.trac.wordpress.org/changeset/3283795/
- https://www.relevanssi.com/user-manual/installing-relevanssi-and-adjusting-the-settings/
- https://www.wordfence.com/threat-intel/vulnerabilities/id/6f77f10b-f142-4859-a941-0fbde6ef7fdb?source=cve
