Auth bypass in Diviengine Divi Membership
CVE-2026-19660
The Divi Membership plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 2.3.0. The `process_paypal_callback` function, hooked to the `init` action, accepts a base64-encoded `paypal_param` GET parameter with no IPN validation, no cryptographic signature check, no ownership verification, and no nonce, allowing it to trust an entirely attacker-controlled user ID value that is passed directly to `wp_set_current_user()` and `wp_set_auth_cookie()`. This makes it possible for unauthenticated attackers to log in as any existing WordPress user — including administrators — by supplying an arbitrary user ID in the `paypal_param` GET parameter, resulting in full site takeover. The vulnerability is further compounded by the fact that the PayPal gateway class is instantiated unconditionally regardless of whether PayPal is enabled or configured, ensuring the vulnerable hook is always registered on every front-end request.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
Frequently asked questions
- What is CVE-2026-19660?
- CVE-2026-19660 is a critical-severity vulnerability in Diviengine Divi Membership, classified under Improper Authentication. CVSS score: 9.8/10. Published 2026-10-02.
- How severe is CVE-2026-19660?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2026-19660 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.