Vulnerability in WP-Members Membership Plugin — CVE-2026-96565
What to do now
Update WP-Members Membership Plugin to 3.5.8 or later.
Affected versions
- Everything up to and including 3.5.7
Affected: WP-Members Membership Plugin (plugin, wp-members)
What the vulnerability is
The WP-Members Membership Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via WooCommerce Checkout Multicheckbox/Multiselect Field (scalar bypass of wpmem_sanitize_array) in all versions up to, and including, 3.5.7 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is only exploitable via the WooCommerce classic checkout path, as the sibling registration, profile, and account-edit handlers implode the value before sanitization, which raises a PHP 8 TypeError on scalar input and fails closed.
Sources
- https://plugins.trac.wordpress.org/browser/wp-members/tags/3.5.7/includes/admin/class-wp-members-admin-users.php#L555
- https://plugins.trac.wordpress.org/browser/wp-members/tags/3.5.7/includes/api/api-forms.php#L372
- https://plugins.trac.wordpress.org/browser/wp-members/tags/3.5.7/includes/api/api-forms.php#L530
- https://plugins.trac.wordpress.org/browser/wp-members/tags/3.5.7/includes/api/api-forms.php#L540
- https://plugins.trac.wordpress.org/browser/wp-members/tags/3.5.7/includes/vendor/rocketgeek-utilities/includes/forms.php#L143
- https://plugins.trac.wordpress.org/browser/wp-members/tags/3.5.8/includes/admin/class-wp-members-admin-users.php