Simple Membership: Cross-site scripting

A Subscriber or higher can store a script payload in the country field that is later rendered without sufficient escaping. An unauthenticated route is also described when Enable Free Membership permits public registration and profile submission; that setting is a prerequisite, not a universal anonymous path. The supplied vector is PR:L. Affected versions: <= 4.8.4. The matching official changelog confirms 4.8.5 as fixed for this CVE.

CVE / CNA score 6.4 CVSS 3.1 · security@wordfence.com

NVD score Pending NVD has not published its own CVSS assessment.

Component: Simple Membership
Plugin slug: simple-membership
Affected: <= 4.8.4
Safe version: 4.8.5
Published: Oct 10, 2026
Weakness: CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

This CVE was published Oct 10, 2026 and is one of 37 known issues for this plugin.

What to do

Update, patch or deactivate.

Update to 4.8.5 or a later supported release. Application-level remediation: Allowlist country values and escape the country field when rendering registration and profile data.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

The Simple Membership plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'country' parameter in all versions up to, and including, 4.8.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Unauthenticated attackers may also exploit this vulnerability when the plugin's Enable Free Membership feature is turned on, as it permits anonymous front-end registration and profile submission.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

References

Primary and upstream sources

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