CVE-2026-1867: WordPress Guest Posting Plugin Vulnerability

CVE-2026-1867 Overview

CVE-2026-1867 is an Information Disclosure vulnerability affecting the Guest posting / Frontend Posting / Front Editor WordPress plugin prior to version 5.0.6. The vulnerability allows unauthenticated attackers to export and download form data and settings, including sensitive information such as administrator email addresses, by manipulating a URL parameter to regenerate a .json file based on demo data.

Critical Impact

Unauthenticated attackers can exfiltrate sensitive administrator email addresses and form configuration data when admin notifications are enabled in the plugin settings.

Affected Products

• Guest posting / Frontend Posting / Front Editor WordPress plugin versions before 5.0.6
• WordPress installations using affected plugin versions with admin notifications enabled
• Sites where administrators have modified the demo form configuration

Discovery Timeline

• 2026-03-11 - CVE-2026-1867 published to NVD
• 2026-03-11 - Last updated in NVD database

Technical Details for CVE-2026-1867

Vulnerability Analysis

This vulnerability is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor). The flaw exists in the plugin's handling of URL parameters that control the regeneration of JSON configuration files. When certain conditions are met—specifically when an administrator has modified the demo form and enabled admin notifications—the plugin fails to properly restrict access to sensitive configuration data.

The attack requires no authentication, making it particularly concerning for exposed WordPress installations. However, exploitation depends on specific configuration conditions being present, which introduces some complexity to successful attacks.

Root Cause

The root cause lies in inadequate access control mechanisms for the JSON file regeneration functionality. The plugin exposes a URL parameter that can trigger the regeneration and subsequent download of configuration files containing sensitive data. The lack of authentication checks on this endpoint allows any remote attacker to invoke this functionality and retrieve the exported data.

Attack Vector

The attack is network-based and can be executed remotely without any user interaction. An attacker can craft a malicious request containing the appropriate URL parameter to trigger the JSON file regeneration process. Once the file is regenerated, the attacker can download it and extract sensitive information including administrator email addresses and complete form data/settings.

The exploitation path involves:

1. Identifying a WordPress site running the vulnerable plugin version
2. Crafting a request with the URL parameter to trigger JSON regeneration
3. Downloading the regenerated .json file containing exported form data
4. Extracting administrator email addresses and configuration details for further attacks

Detection Methods for CVE-2026-1867

Indicators of Compromise

• Unusual HTTP requests targeting plugin endpoints with URL parameters designed to regenerate JSON files
• Unexpected access to .json files within the plugin directory structure
• Multiple requests from single IP addresses probing for plugin configuration endpoints
• Log entries showing successful downloads of form configuration files by unauthenticated users

Detection Strategies

• Monitor web server access logs for requests containing suspicious URL parameters targeting the Guest Posting plugin endpoints
• Implement web application firewall (WAF) rules to detect and block requests attempting to access plugin configuration files
• Set up alerts for downloads of .json files from plugin directories by unauthenticated sessions
• Review plugin directory permissions and file access patterns regularly

Monitoring Recommendations

• Enable detailed logging for the WordPress plugins directory to track file access and regeneration events
• Configure SIEM rules to correlate multiple reconnaissance attempts against WordPress plugin endpoints
• Establish baseline behavior for legitimate plugin operations to identify anomalous activity
• Monitor for unauthorized enumeration of WordPress plugin versions and configurations

How to Mitigate CVE-2026-1867

Immediate Actions Required

• Update the Guest posting / Frontend Posting / Front Editor WordPress plugin to version 5.0.6 or later immediately
• Review plugin settings and disable admin notifications if not required until patching is complete
• Audit access logs for any signs of exploitation or reconnaissance activity
• Consider temporarily deactivating the plugin if an immediate update is not possible

Patch Information

The vulnerability has been addressed in version 5.0.6 of the Guest posting / Frontend Posting / Front Editor WordPress plugin. Administrators should update to this version or later through the WordPress plugin management interface. For detailed vulnerability information, refer to the WPScan Vulnerability Report.

Workarounds

• Restrict access to plugin endpoints using web server configuration rules or WAF policies
• Disable admin notification features in the plugin settings until the update can be applied
• Implement additional authentication layers for WordPress admin areas
• Remove or reset any demo form configurations that may contain sensitive data

# Example: Block access to plugin JSON files via .htaccess
<FilesMatch "\.json$">
    <IfModule mod_authz_core.c>
        Require all denied
    </IfModule>
    <IfModule !mod_authz_core.c>
        Order deny,allow
        Deny from all
    </IfModule>
</FilesMatch>