The Paid Membership Subscriptions – Effortless Memberships, Recurring Payments & Content Restriction plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 2.13.7. This is due to the pms_pb_payment_redirect_link function using the user-controlled value supplied via the 'pms_payment_id' parameter to authenticate users without any further identity validation. This makes it possible for unauthenticated attackers with knowledge of a valid payment ID to log in as any user who has made a purchase on the targeted site.

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE-287

https://plugins.trac.wordpress.org/changeset/3214706/paid-member-subscriptions

https://www.wordfence.com/threat-intel/vulnerabilities/id/d3a4fa4d-a7d2-4890-b0f5-5fe69bc5e7ac?source=cve