CVE-2025-6688
📋 TL;DR
The Simple Payment WordPress plugin contains an authentication bypass vulnerability that allows unauthenticated attackers to log in as administrative users. This affects WordPress sites running Simple Payment plugin versions 1.3.6 through 2.3.8. Attackers can gain full administrative control of vulnerable WordPress installations.
💻 Affected Systems
- Simple Payment WordPress Plugin
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete site takeover with administrative privileges, allowing data theft, malware injection, defacement, and creation of backdoor accounts.
Likely Case
Unauthorized administrative access leading to data compromise, plugin/theme manipulation, and potential lateral movement within the hosting environment.
If Mitigated
Limited impact if proper network segmentation, strong authentication, and monitoring are in place to detect unauthorized access attempts.
🎯 Exploit Status
The vulnerability is in the create_user() function which doesn't properly verify user identity before login.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.3.9
Vendor Advisory: https://plugins.trac.wordpress.org/changeset/3318371/simple-payment/tags/2.3.9/simple-payment-plugin.php
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins > Installed Plugins. 3. Find Simple Payment plugin. 4. Click 'Update Now' if available, or manually update to version 2.3.9. 5. Verify the plugin is active on version 2.3.9.
🔧 Temporary Workarounds
Disable Simple Payment Plugin
linuxTemporarily disable the vulnerable plugin until patching is possible.
wp plugin deactivate simple-payment
Restrict Access to WordPress Admin
allImplement IP whitelisting for WordPress admin area to limit attack surface.
🧯 If You Can't Patch
- Remove Simple Payment plugin completely from the WordPress installation
- Implement web application firewall rules to block authentication bypass attempts
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel > Plugins > Simple Payment version. If version is between 1.3.6 and 2.3.8 inclusive, the system is vulnerable.Check Version:
wp plugin get simple-payment --field=versionVerify Fix Applied:
Confirm Simple Payment plugin version is 2.3.9 or higher in WordPress admin panel.📡 Detection & Monitoring
Log Indicators:
- Unusual admin login attempts from new IP addresses
- Multiple failed login attempts followed by successful admin login
- User creation or privilege escalation events in WordPress logs
Network Indicators:
- HTTP POST requests to WordPress login or user creation endpoints with suspicious parameters
- Traffic patterns indicating authentication bypass attempts
SIEM Query:
source="wordpress" AND (event="user_login" OR event="wp_login") AND user_role="administrator" AND src_ip NOT IN (allowed_admin_ips)