CVE-2026-11855
High
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.
SeverityHigh
CVSS8.8
Exploit probability—
ProductSimple Membership
PublishedJul 6, 2026
First seenJul 6, 2026
Weakness typeCWE-79Cross-site scripting (XSS)
How to fix
Update
- Simple Membership4.7.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Simple Membership | v < 4.7.5 | 4.7.5 |
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