CVE-2025-66073
📋 TL;DR
This vulnerability allows attackers to inject malicious objects through deserialization of untrusted data in the WP Webhooks WordPress plugin. Attackers could execute arbitrary code, potentially compromising the entire WordPress site. All WordPress installations using WP Webhooks version 3.3.8 or earlier are affected.
💻 Affected Systems
- WP Webhooks 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
Complete site takeover with remote code execution, data theft, and server compromise leading to lateral movement within the hosting environment.
Likely Case
Unauthenticated attackers gain administrative access to WordPress, install backdoors, deface sites, or steal sensitive data.
If Mitigated
Attack limited to plugin functionality with proper input validation and output encoding in place.
🎯 Exploit Status
Public exploit details available on security research sites, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.3.9 or later
Restart Required: No
Instructions:
1. Log into WordPress admin panel
2. Navigate to Plugins → Installed Plugins
3. Find WP Webhooks plugin
4. Click 'Update Now' if update available
5. If no update appears, manually download version 3.3.9+ from WordPress.org
6. Deactivate old plugin, upload new version, activate
🔧 Temporary Workarounds
Disable WP Webhooks Plugin
allTemporarily disable the vulnerable plugin until patched
wp plugin deactivate wp-webhooks
Restrict Webhook Access
linuxBlock external access to webhook endpoints via web server configuration
# Add to .htaccess for Apache:
<FilesMatch "wp-webhooks">
Order Deny,Allow
Deny from all
</FilesMatch>
# Add to nginx config:
location ~* wp-webhooks {
deny all;
}
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block deserialization attacks
- Disable PHP object unserialize functionality via php.ini (allow_url_include=Off, disable_functions=unserialize)
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin → Plugins → WP Webhooks version number. If version is 3.3.8 or lower, you are vulnerable.Check Version:
wp plugin get wp-webhooks --field=versionVerify Fix Applied:
Verify WP Webhooks version is 3.3.9 or higher in WordPress admin plugins page.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /wp-content/plugins/wp-webhooks/ endpoints
- PHP unserialize errors in web server logs
- Unexpected admin user creation in WordPress logs
Network Indicators:
- HTTP requests with serialized PHP objects in POST data
- Traffic to known exploit patterns for CVE-2025-66073
SIEM Query:
source="web_server" AND (uri="*wp-webhooks*" OR post_data="*O:*" OR post_data="*C:*")