Description
The Simple Membership plugin for WordPress is vulnerable to Improper Handling of Missing Values in all versions up to, and including, 4.7.0 via the Stripe webhook handler. This is due to the plugin only validating webhook signatures when the stripe-webhook-signing-secret setting is configured, which is empty by default. This makes it possible for unauthenticated attackers to forge Stripe webhook events to manipulate membership subscriptions, including reactivating expired memberships without payment or canceling legitimate subscriptions, potentially leading to unauthorized access and service disruption.
CVSS breakdown
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None
Affected products
- wpinsider-1 / Simple Membership0 – 4.7.0
References
- MISChttps://www.wordfence.com/threat-intel/vulnerabilities/id/4e4df9a6-8f7d-428b-a596-0751ca047169?source=cve
- MISChttps://plugins.trac.wordpress.org/browser/simple-membership/trunk/ipn/swpm-stripe-webhook-handler.php#L26
- MISChttps://plugins.trac.wordpress.org/browser/simple-membership/trunk/classes/class.swpm-wp-loaded-tasks.php#L90
- MISChttps://plugins.trac.wordpress.org/changeset/3453404/