CVE-2026-2126
📋 TL;DR
This vulnerability allows unauthenticated attackers to bypass category restrictions in the User Submitted Posts WordPress plugin. Attackers can assign user-submitted posts to arbitrary categories, including restricted ones, by manipulating POST requests. All WordPress sites using vulnerable versions of this plugin are affected.
💻 Affected Systems
- User Submitted Posts – Enable Users to Submit Posts from the Front End 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 post content to sensitive or restricted categories, potentially exposing confidential information, spreading misinformation, or violating content policies.
Likely Case
Unauthorized posts appearing in categories they shouldn't, potentially bypassing moderation workflows or content filtering.
If Mitigated
With proper monitoring and category-level permissions, impact is limited to unauthorized category assignments that can be detected and corrected.
🎯 Exploit Status
Exploitation requires crafting a direct POST request with manipulated user-submitted-category[] values, which is straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 20260113
Restart Required: No
Instructions:
1. Log into WordPress admin panel
2. Navigate to Plugins → Installed Plugins
3. Find 'User Submitted Posts'
4. Click 'Update Now' if available
5. If no update appears, manually download latest version from WordPress plugin repository
6. Deactivate, delete old version, upload and activate new version
🔧 Temporary Workarounds
Disable plugin
allTemporarily disable the User Submitted Posts plugin until patched
wp plugin deactivate user-submitted-posts
Web Application Firewall rule
allBlock POST requests containing manipulated user-submitted-category[] parameters
🧯 If You Can't Patch
- Implement strict input validation at the web server level to reject POST requests with unexpected category parameters
- Enable detailed logging of all user submissions and implement automated alerts for category assignment anomalies
🔍 How to Verify
Check if Vulnerable:
Check plugin version in WordPress admin panel under Plugins → Installed Plugins. If version is 20260113 or earlier, you are vulnerable.Check Version:
wp plugin get user-submitted-posts --field=versionVerify Fix Applied:
After updating, verify the plugin version is newer than 20260113. Test submission functionality to ensure categories are properly restricted.📡 Detection & Monitoring
Log Indicators:
- POST requests to submission endpoints with unexpected category IDs
- Posts appearing in categories not configured for user submissions
Network Indicators:
- HTTP POST requests containing user-submitted-category[] parameters with non-allowed values
SIEM Query:
source="wordpress" AND (http_method="POST" AND uri_path="/wp-admin/admin-ajax.php" AND post_data CONTAINS "user-submitted-category")🔗 References
- https://plugins.trac.wordpress.org/browser/user-submitted-posts/tags/20260113/user-submitted-posts.php#L1431
- https://plugins.trac.wordpress.org/browser/user-submitted-posts/tags/20260113/user-submitted-posts.php#L298
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3463696%40user-submitted-posts%2Ftrunk&old=3456521%40user-submitted-posts%2Ftrunk&sfp_email=&sfph_mail=
- https://www.wordfence.com/threat-intel/vulnerabilities/id/02c5e3ad-5cc3-40b1-a15a-10d53383abe6?source=cve
