CVE-2026-11964: critical vulnerability in User Registration & Membership
User Registration & Membership < 5.2.2 - Unauthenticated PayPal Webhook Signature Verification Bypass Leading to Membership Activation
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
48Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 9.1epss 0.5%
The User Registration & Membership WordPress plugin before 5.2.2 does not verify the authenticity of incoming payment-provider webhook notifications before acting on them, allowing unauthenticated attackers to forge a payment-approved event and activate a paid membership subscription without completing a real payment.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Unknown · User Registration & Membershippublic PoCs found — 1
cve_referencewpscan.com/vulnerability/faf55649-8f76-4abf-a6b9-0d0774e22d29/unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — User Registration & Membership
In the same product, most dangerous first.
CVE-2025-2563HIGHUser Registration & Membership < 4.1.2- Unauthenticated Privilege EscalationEPSS 49.1%CVE-2025-2594HIGHUser Registration & Membership < 4.1.3 - Authentication BypassEPSS 9.5%CVE-2026-80071HIGHUser Registration & Membership < 5.2.8 - Author+ Privilege Escalation to AdministratorEPSS 0.5%CVE-2026-79996HIGHUser Registration & Membership < 5.2.6 - Authenticated Privilege Escalation via Login SettingsEPSS 0.5%CVE-2026-16736HIGHUser Registration & Membership < 5.2.6 - Unauthenticated Account Creation While Registration DisabledEPSS 0.4%CVE-2026-11961HIGHUser Registration & Membership < 5.2.3 - Unauthenticated Privilege Escalation via Unbound members_data Membership IDEPSS 0.4%