CVE-2026-73396 Overview
CVE-2026-73396 is a broken authentication vulnerability in the MWB HubSpot for WooCommerce WordPress plugin versions 1.6.7 and earlier. The flaw allows authenticated users with subscriber-level privileges to bypass authentication controls and perform actions beyond their intended authorization scope. The vulnerability is classified under [CWE-288] (Authentication Bypass Using an Alternate Path or Channel).
The issue affects WooCommerce stores that integrate with HubSpot through the MakeWebBetter plugin. Successful exploitation can compromise data integrity and lead to availability impact on the affected WordPress site.
Critical Impact
Authenticated subscribers can bypass authentication logic in the MWB HubSpot for WooCommerce plugin, enabling unauthorized modification of plugin data and potential denial of service against WooCommerce store operations.
Affected Products
- MWB HubSpot for WooCommerce plugin versions 1.6.7 and earlier
- WordPress sites running the MakeWebBetter HubSpot for WooCommerce integration
- WooCommerce installations with HubSpot synchronization enabled through this plugin
Discovery Timeline
- 2026-08-18 - CVE-2026-73396 published to NVD
- 2026-08-20 - Last updated in NVD database
Technical Details for CVE-2026-73396
Vulnerability Analysis
The MWB HubSpot for WooCommerce plugin contains a broken authentication flaw that fails to properly validate the identity of authenticated users before performing sensitive operations. Attackers holding subscriber accounts, the lowest privileged WordPress role, can leverage this weakness to reach functionality intended for higher-privileged users.
The vulnerability requires network access and low attack complexity. An attacker needs only a valid subscriber account, which many WordPress sites permit through open registration. No user interaction is required to trigger the flaw.
Successful exploitation results in low integrity impact and high availability impact. Attackers can manipulate plugin state or trigger conditions that disrupt store operations connected to HubSpot.
Root Cause
The root cause is improper authentication logic within plugin endpoints. The plugin fails to enforce role-based access controls consistently across its request handlers. This maps to [CWE-288], where an alternate path or channel bypasses the intended authentication mechanism.
Attack Vector
An attacker authenticates to the WordPress site using a subscriber account. The attacker then issues crafted HTTP requests to plugin endpoints that should require elevated privileges. Because authentication verification is missing or incomplete, the plugin processes these requests as if they originated from authorized users. Technical exploitation details are documented in the PatchStack Vulnerability Report.
Detection Methods for CVE-2026-73396
Indicators of Compromise
- Unexpected HTTP POST or GET requests from subscriber accounts to /wp-admin/admin-ajax.php or plugin-specific endpoints referencing mwb or hubspot action parameters
- Anomalous changes to HubSpot synchronization settings or WooCommerce plugin configuration without corresponding administrator activity
- WordPress audit log entries showing subscriber-role users accessing administrative plugin functionality
Detection Strategies
- Deploy WordPress security plugins that log AJAX and REST API calls, then correlate subscriber account activity against expected role permissions
- Monitor web server access logs for repeated requests to MWB HubSpot for WooCommerce endpoints originating from low-privilege sessions
- Alert on any modification of plugin configuration tables in the WordPress database initiated by non-administrator users
Monitoring Recommendations
- Enable verbose logging for authentication events and privileged plugin actions across the WordPress installation
- Track subscriber account creation patterns for spikes that may indicate preparation for exploitation
- Forward WordPress and web server logs to a centralized SIEM for correlation and long-term retention
How to Mitigate CVE-2026-73396
Immediate Actions Required
- Update the MWB HubSpot for WooCommerce plugin to a version above 1.6.7 as soon as a fixed release is published
- Audit subscriber accounts on the affected WordPress site and remove suspicious or unused registrations
- Restrict new user registration if the site does not require public subscriber accounts
Patch Information
Refer to the PatchStack Vulnerability Report for the latest fixed version and vendor guidance. Apply the plugin update through the WordPress admin dashboard or via WP-CLI.
Workarounds
- Temporarily deactivate the MWB HubSpot for WooCommerce plugin until a patched version is available
- Apply a web application firewall rule to block requests to plugin endpoints from users below the administrator role
- Disable open user registration by setting Anyone can register to off under WordPress general settings to prevent attackers from creating subscriber accounts
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
