CVE-2026-3688
The WCFM Membership – WooCommerce Memberships for Multivendor Marketplace plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 2.11.10. This is due to the 'wcfmvm_membership_change' AJAX action not validating user permission to modify other users. This makes it possible for authenticated attackers, with vendor level access and above, to change any user's role to 'wcfm_vendor' by changing their membership plan.
No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 3.1 : 8.1 HIGH
Vector: AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.