Vulnerability · Published Jul 6, 2026 · Assigned by WPScan
CVE-2026-11855Simple Membership < 4.7.5 - Unauthenticated Stored XSS via Stripe Webhook API Version
High 8.8
In plain English
A high-severity security flaw in Simple Membership from Unknown. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities).
Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.5%top 56.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
The Simple Membership WordPress plugin before 4.7.5 does not verify the authenticity of Stripe webhook requests when no signing secret is configured, nor escape a value taken from them before outputting it in an administrator notice, allowing unauthenticated attackers to inject arbitrary web scripts that execute in the context of a logged-in administrator.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Unknown | Simple Membership | 0 – before 4.7.5 |
References
- https://wpscan.com/vulnerability/217cb606-a0f2-4427-9262-cfe1cc90474e/ exploit, vdb-entry, technical-description