CVE-2026-39662: WooCommerce Formula Plugin Auth Bypass

CVE-2026-39662 Overview

CVE-2026-39662 is a Missing Authorization vulnerability in the Product Price by Formula for WooCommerce plugin developed by ProWCPlugins. This WordPress plugin is designed to allow store owners to dynamically calculate product prices using custom formulas. The vulnerability exists due to improperly configured access control security levels, which allows unauthorized users to exploit these misconfigured access controls and potentially access sensitive pricing information.

Critical Impact

Unauthorized network-based attackers can exploit this broken access control vulnerability to gain access to confidential pricing data without authentication, potentially exposing business-sensitive information to competitors or malicious actors.

Affected Products

• Product Price by Formula for WooCommerce versions up to and including 2.5.6
• WordPress installations running the vulnerable product-price-by-formula-for-woocommerce plugin
• WooCommerce stores utilizing dynamic pricing formulas through this plugin

Discovery Timeline

• April 8, 2026 - CVE-2026-39662 published to NVD
• April 9, 2026 - Last updated in NVD database

Technical Details for CVE-2026-39662

Vulnerability Analysis

This vulnerability falls under CWE-862 (Missing Authorization), a classification for security flaws where software fails to perform authorization checks when an actor attempts to access a resource or perform an action. In the context of the Product Price by Formula for WooCommerce plugin, certain endpoints or functions lack proper capability checks, allowing unauthenticated or low-privileged users to access functionality that should be restricted to administrators or authorized personnel only.

The attack is network-accessible, requires no privileges or user interaction, and can result in unauthorized disclosure of confidential information. While the vulnerability does not directly allow for data modification or service disruption, the exposure of pricing formulas and related business logic could have significant commercial implications for affected e-commerce stores.

Root Cause

The root cause of this vulnerability is the absence of proper authorization checks within the plugin's codebase. WordPress plugins typically use capability checks (such as current_user_can()) and nonce verification to ensure that only authorized users can access specific functionality. In this case, the plugin fails to implement these security controls on certain endpoints or AJAX actions, allowing any user—authenticated or not—to access protected resources.

This is a common pattern in WordPress plugin vulnerabilities where developers assume that obscurity or the complexity of finding an endpoint provides sufficient protection, rather than implementing explicit authorization controls.

Attack Vector

The vulnerability can be exploited remotely over the network without requiring any authentication credentials or user interaction. An attacker can directly access the vulnerable endpoints by crafting HTTP requests to the WordPress installation running the affected plugin.

The attack scenario typically involves:

1. Identifying a WordPress site running the Product Price by Formula for WooCommerce plugin version 2.5.6 or earlier
2. Sending unauthenticated requests to exposed AJAX handlers or REST API endpoints
3. Extracting sensitive pricing formulas, configuration data, or other protected information

For detailed technical information about the exploitation mechanism, refer to the Patchstack Vulnerability Report.

Detection Methods for CVE-2026-39662

Indicators of Compromise

• Unusual HTTP requests to AJAX endpoints associated with the product-price-by-formula-for-woocommerce plugin from unauthenticated sources
• Access logs showing repeated requests to pricing formula endpoints without corresponding admin session cookies
• Unexpected external IP addresses querying WooCommerce pricing-related endpoints
• Increased traffic patterns targeting the wp-admin/admin-ajax.php endpoint with plugin-specific actions

Detection Strategies

• Implement Web Application Firewall (WAF) rules to monitor and log requests to the vulnerable plugin endpoints
• Configure WordPress security plugins to alert on unauthorized access attempts to admin-only functionality
• Review server access logs for suspicious patterns targeting the product-price-by-formula-for-woocommerce plugin paths
• Deploy endpoint detection solutions capable of identifying broken access control exploitation attempts

Monitoring Recommendations

• Enable detailed logging for WordPress AJAX requests and monitor for anomalous access patterns
• Set up alerts for high-volume requests to pricing-related endpoints from single IP addresses or user agents
• Monitor plugin activity logs for unauthorized access to formula configuration pages
• Implement real-time security monitoring with SentinelOne Singularity to detect exploitation attempts

How to Mitigate CVE-2026-39662

Immediate Actions Required

• Update the Product Price by Formula for WooCommerce plugin to the latest patched version immediately
• If an update is not available, temporarily deactivate the plugin until a security patch is released
• Review access logs to determine if the vulnerability has been exploited prior to patching
• Conduct a security audit of other installed WordPress plugins for similar access control issues

Patch Information

Organizations should monitor the official WordPress plugin repository and the Patchstack Vulnerability Report for updates regarding a patched version. Users are strongly advised to upgrade beyond version 2.5.6 once a security fix is available from ProWCPlugins.

Workarounds

• Temporarily disable the Product Price by Formula for WooCommerce plugin if it is not critical to operations
• Implement server-level access restrictions to limit requests to vulnerable endpoints to authenticated admin users only
• Use a WordPress security plugin or WAF to block unauthenticated requests to the plugin's AJAX handlers
• Consider implementing IP whitelisting for administrative functionality as an additional layer of protection

# Apache .htaccess workaround to restrict access to admin-ajax.php for specific actions
# Add to WordPress root .htaccess file
<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteCond %{REQUEST_URI} ^/wp-admin/admin-ajax\.php$ [NC]
  RewriteCond %{QUERY_STRING} action=ppbf_ [NC]
  RewriteCond %{HTTP_COOKIE} !wordpress_logged_in [NC]
  RewriteRule .* - [F,L]
</IfModule>