CVE-2026-11964
CRITICAL
Published Jul 13, 2026
Modified Jul 13, 2026
Description
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.
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CVSS v3.1 Score
9.1
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS — Exploit Prediction
0.0028
Probability of exploitation
0.20%
Percentile rank
EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.
References
Frequently Asked Questions
What is CVE-2026-11964? +
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. It has a CVSS v3.1 base score of 9.1 (CRITICAL).
How severe is CVE-2026-11964? +
CVE-2026-11964 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0028, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-11964? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.
