CVE-2026-0726
📋 TL;DR
The Nexter Extension plugin for WordPress has a PHP object injection vulnerability that allows unauthenticated attackers to inject malicious PHP objects via deserialization of untrusted input. This vulnerability only becomes dangerous when combined with another plugin or theme containing a POP (Property-Oriented Programming) chain. All WordPress sites using this plugin up to version 4.4.6 are affected.
💻 Affected Systems
- Nexter Extension – Site Enhancements Toolkit 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
If combined with a suitable POP chain from another plugin/theme, attackers could achieve remote code execution, file deletion, or data exfiltration, potentially compromising the entire WordPress site.
Likely Case
Most sites will experience no impact unless they have specific vulnerable plugins/themes installed that provide usable POP chains. The vulnerability alone cannot be exploited without additional vulnerable components.
If Mitigated
With proper plugin management and security controls, the risk is minimal as the vulnerability requires specific conditions to be exploitable.
🎯 Exploit Status
Exploitation requires finding or creating a suitable POP chain from other installed components. No known POP chain exists in the vulnerable plugin itself.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.4.7
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'Nexter Extension – Site Enhancements Toolkit'. 4. Click 'Update Now' if available, or manually update to version 4.4.7+. 5. Verify the update completed successfully.
🔧 Temporary Workarounds
Disable vulnerable plugin
allTemporarily disable the Nexter Extension plugin until patching is possible
wp plugin deactivate nexter-extension
Remove plugin files
linuxCompletely remove the vulnerable plugin from the WordPress installation
rm -rf /path/to/wordpress/wp-content/plugins/nexter-extension/
🧯 If You Can't Patch
- Implement a web application firewall (WAF) with rules to block PHP object injection attempts
- Audit and remove any unnecessary plugins/themes that could provide POP chains for exploitation
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel → Plugins → Installed Plugins for 'Nexter Extension' version 4.4.6 or lowerCheck Version:
wp plugin get nexter-extension --field=versionVerify Fix Applied:
Verify the plugin version shows 4.4.7 or higher in WordPress admin panel📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to WordPress endpoints containing serialized PHP objects
- Errors related to deserialization in PHP/WordPress logs
Network Indicators:
- HTTP requests containing serialized data patterns to WordPress admin or plugin-specific endpoints
SIEM Query:
source="wordpress.log" AND ("nxt_unserialize_replace" OR "PHP object injection" OR "unserialize")🔗 References
- https://plugins.trac.wordpress.org/changeset?old_path=/nexter-extension/tags/4.4.6/include/panel-settings/extensions/nexter-ext-replace-url.php&new_path=/nexter-extension/tags/4.4.7/include/panel-settings/extensions/nexter-ext-replace-url.php
- https://www.wordfence.com/threat-intel/vulnerabilities/id/02de9287-68e4-46ce-a491-3f6cbb7fc0ed?source=cve
