CVE-2026-11964
Unauthenticated webhook forgery can activate paid memberships.
Is CVE-2026-11964 being exploited?
Not confirmed. CVE-2026-11964 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.45% probability of exploitation in the next 30 days.
How severe is CVE-2026-11964?
CVE-2026-11964 is rated Critical with a CVSS score of 9.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-11964?
Yes. A fix has been recorded for CVE-2026-11964. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-11964 affect?
CVE-2026-11964 affects User Registration & Membership WordPress plugin (< 5.2.2), Self-hosted WordPress sites using that plugin. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-11964?
Update plugin to 5.2.2 and verify webhook signature validation
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Attackers can forge payment-provider webhooks to activate paid memberships without payment, granting unauthorized access and causing revenue loss.
Immediate action required
- affected< 5.2.2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.