CVE-2026-88764

Simple Membership < 4.7.8 - Subscriber+ Membership Level Escalation via PayPal Standard subsc_ref

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.

Affected

Simple Membership

CVSS v3.1 CNA

5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

EPSS

0.23% chance of exploitation in the next 30 days, 13th percentile

Published

2026-09-13

Proof-of-concept exploits (1)

• https://wpscan.com/vulnerability/54fdf46e-0385-40a3-b3bc-a862dc0fb03e/

References

• CVE Record
• NVD entry