Simple Membership trusts a mismatched PayPal membership level
Simple Membership versions before 4.7.8 do not verify that the membership level in a PayPal payment notification matches the level configured for the paid button. A member can pay the price of a lower tier while supplying a higher, more privileged membership level and receive the stronger membership. The authoritative export does not identify the notification endpoint, membership-level field, or button identifier.
- Component
- Simple Membership
- Plugin slug
simple-membership- Affected
- < 4.7.8
- Safe version
4.7.8- Published
- Sep 13, 2026
This CVE was published Sep 13, 2026 and is one of 34 known issues for this plugin.
Update, patch or deactivate.
Update Simple Membership to 4.7.8 or later. The application-level fix must derive the granted membership from server-side button and transaction data, validate the PayPal notification and payment amount, and reject any client-supplied level that does not match the purchased product.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The Simple Membership WordPress plugin before 4.7.8 does not validate that the membership level supplied in a PayPal payment notification matches the level configured for the paid payment button, allowing members to pay for a lower-priced membership while being granted a higher, more privileged membership level.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N