CVE-2026-1000: MailerLite WooCommerce Auth Bypass Flaw

CVE-2026-1000 Overview

The MailerLite - WooCommerce integration plugin for WordPress contains a Missing Authorization vulnerability (CWE-862) that allows authenticated attackers with minimal privileges to perform unauthorized data modification and deletion. All versions up to and including 3.1.3 are affected due to missing capability checks on the resetIntegration() function. This vulnerability enables attackers with Subscriber-level access or above to reset the plugin's integration settings, delete all plugin options, and drop critical database tables, resulting in complete loss of plugin data.

Critical Impact

Authenticated attackers with Subscriber-level access can completely wipe plugin data including the woo_mailerlite_carts and woo_mailerlite_jobs database tables, resulting in permanent loss of customer abandoned cart information and sync job history.

Affected Products

• MailerLite - WooCommerce integration plugin for WordPress versions ≤ 3.1.3
• WordPress installations with the woo-mailerlite plugin installed
• WooCommerce stores utilizing MailerLite integration for email marketing

Discovery Timeline

• January 16, 2026 - CVE-2026-1000 published to NVD
• January 16, 2026 - Last updated in NVD database

Technical Details for CVE-2026-1000

Vulnerability Analysis

This vulnerability stems from improper access control implementation within the MailerLite WooCommerce plugin's administrative functions. The resetIntegration() function in WooMailerLiteAdminSettingsController.php lacks proper capability checks, allowing any authenticated user—regardless of their WordPress role—to execute destructive administrative operations.

The vulnerability is particularly dangerous because WordPress Subscriber accounts are often created through public registration or e-commerce checkout processes, making this attack surface readily accessible on many WooCommerce installations. An attacker exploiting this flaw can completely disrupt a store's email marketing integration and destroy valuable customer behavior data.

Root Cause

The root cause is a Missing Authorization vulnerability (CWE-862) in the plugin's resetIntegration() function located in WooMailerLiteAdminSettingsController.php at line 231. The function fails to verify that the requesting user has appropriate administrative capabilities before executing sensitive operations. WordPress plugins must implement proper capability checks using functions like current_user_can() to ensure only authorized administrators can perform destructive actions like resetting integrations or dropping database tables.

Attack Vector

The attack leverages the network-accessible WordPress AJAX or REST API endpoints to invoke the vulnerable resetIntegration() function. An attacker needs only valid Subscriber-level credentials to authenticate to the WordPress installation. Once authenticated, they can send a crafted request to trigger the function, which will:

1. Reset all MailerLite integration settings to defaults
2. Delete all plugin-specific WordPress options from the wp_options table
3. Drop the woo_mailerlite_carts database table containing abandoned cart data
4. Drop the woo_mailerlite_jobs database table containing synchronization job history

The vulnerable code path can be traced through the WooMailerLite Include File which initializes the controller, and the WooMailerLite Migration File which handles the database table operations. The lack of authorization checks at the controller level allows these operations to be triggered without proper permission validation.

Detection Methods for CVE-2026-1000

Indicators of Compromise

• Unexpected reset of MailerLite integration settings without administrator action
• Missing or empty woo_mailerlite_carts and woo_mailerlite_jobs database tables
• WordPress audit logs showing resetIntegration calls from non-administrator accounts
• Sudden loss of abandoned cart data and email sync job history

Detection Strategies

• Monitor WordPress AJAX and REST API requests for calls to MailerLite reset functions from non-admin users
• Implement database activity monitoring to detect DROP TABLE operations on woo_mailerlite_* tables
• Review WordPress user activity logs for Subscriber accounts making administrative plugin requests
• Set up alerts for bulk deletion of wp_options entries with mailerlite or woo_mailerlite prefixes

Monitoring Recommendations

• Enable comprehensive WordPress audit logging to track all plugin-related administrative actions
• Configure database-level monitoring for DDL statements targeting plugin tables
• Implement real-time alerting for unexpected plugin setting changes
• Regularly verify the integrity of MailerLite integration configuration and associated database tables

How to Mitigate CVE-2026-1000

Immediate Actions Required

• Update the MailerLite - WooCommerce integration plugin to a version newer than 3.1.3 immediately
• Review WordPress user accounts and remove unnecessary Subscriber accounts or disable public registration
• Audit recent WordPress activity logs for any suspicious resetIntegration function calls
• Create backups of the woo_mailerlite_carts and woo_mailerlite_jobs database tables

Patch Information

A security patch has been released for this vulnerability. The fix can be reviewed in the WordPress WooMailerLite Changeset which adds proper capability checks to the resetIntegration() function. Site administrators should update through the WordPress plugin update mechanism or manually download the patched version from the WordPress plugin repository. For additional details, consult the Wordfence Vulnerability Report.

Workarounds

• Temporarily disable the MailerLite - WooCommerce plugin until the update can be applied
• Restrict WordPress user registration to prevent unauthorized account creation
• Implement a Web Application Firewall (WAF) rule to block requests to the vulnerable endpoint from non-admin users
• Use a security plugin to enforce capability checks on AJAX and REST API requests

# Configuration example - Backup MailerLite plugin tables before remediation
# Export woo_mailerlite tables for backup
wp db export --tables=woo_mailerlite_carts,woo_mailerlite_jobs mailerlite_backup.sql

# Update the plugin to the latest patched version
wp plugin update woo-mailerlite

# Verify the update was successful
wp plugin get woo-mailerlite --field=version