Auth bypass in Properfraction Paid Membership Plugin, Ecommerce, User Registration Form, Login Profile & Restrict Content – Profilepress

CVE-2026-3453

The ProfilePress plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.16.11. This is due to missing ownership validation on the change_plan_sub_id parameter in the process_checkout() function. The ppress_process_checkout AJAX handler accepts a user-controlled subscription ID intended for plan upgrades, loads the subscription record, and cancels/expires it without verifying the subscription belongs to the requesting user. This makes it possible for authenticated attackers, with Subscriber-level access and above, to cancel and expire any other user's active subscription via the change_plan_sub_id parameter during checkout, causing immediate loss of paid access for victims.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (33.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-3453: held from 0.005 to 0.004.

EPSS over last 30 days · oldest: 0.005 · newest: 0.004 · change: -0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3453?
CVE-2026-3453 is a high-severity vulnerability in Properfraction Paid Membership Plugin, Ecommerce, User Registration Form, Login Profile & Restrict Content – Profilepress, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.1/10. Published 2026-03-11.
How severe is CVE-2026-3453?
High severity. CVSS v3 base score is 8.1 out of 10.