Stored cross-site scripting in User Registration & Membership plugin
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
The User Registration & Membership plugin for WordPress is affected in all versions up to and including 5.2.8. Insufficient input sanitization and output escaping of checkbox field values allows stored cross-site scripting (CWE-79). An unauthenticated attacker can inject arbitrary web scripts into pages that execute whenever a user accesses an injected page.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
The User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Checkbox Field Value in all versions up to, and including, 5.2.8 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The nopriv AJAX action user_registration_user_form_submit reaches ur_process_registration() without nonce validation, meaning any unauthenticated request can reach the vulnerable code path.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| wpeverest | User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder | up to 5.2.8 | — | No fix listed | CNA |
- User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder Vendorwpeverest Affected up to 5.2.8 Fixed in — No fix listed CNA
Remediation
The sources list no fixed version for User Registration & Membership.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Timeline
- 2026-10-18 Threatist record created from CVE-2026-96660
- 2026-10-18 Alias added: GHSA-mc7j-c3xf-rrxf
References
Other 6
- https://www.wordfence.com/threat-intel/vulnerabilities/id/690d23ee-cf70-4ecf-8cd2-21f673788d5f?source=cve
- https://plugins.trac.wordpress.org/browser/user-registration/tags/5.2.8/includes/functions-ur-template.php#L555
- https://plugins.trac.wordpress.org/browser/user-registration/tags/5.2.8/includes/frontend/class-ur-frontend-form-handler.php#L519
- https://plugins.trac.wordpress.org/browser/user-registration/tags/5.2.8/includes/class-ur-ajax.php#L221
- https://plugins.trac.wordpress.org/browser/user-registration/tags/5.2.8/includes/functions-ur-core.php#L5606
- https://plugins.trac.wordpress.org/changeset/3741339/user-registration/trunk/includes/frontend/class-ur-frontend-form-handler.php
More wpeverest vulnerabilities
- TI-2025-00958 Everest Forms <= 3.0.9.4 - Unauthenticated Arbitrary File Upload, Read, and Deletion CVSS 3.1CRITICAL 9.8
- TI-2026-02850 Everest Forms Pro <= 1.9.12 - Unauthenticated Remote Code Execution via Calculation Field CVSS 3.1CRITICAL 9.8
- TI-2026-01188 User Registration & Membership <= 5.1.2 - Unauthenticated Privilege Escalation via Membership Registration CVSS 3.1CRITICAL 9.8
- TI-2025-02262 User Registration & Membership < 4.1.3 - Authentication Bypass CVSS 3.1HIGH 8.1
- TI-2025-02232 User Registration & Membership < 4.1.2- Unauthenticated Privilege Escalation CVSS 3.1HIGH 8.1
- TI-2022-03588 User Registration < 2.2.4.1 - Subscriber+ Arbitrary File Upload CVSS 3.1HIGH 7.5
Sources
- CVE-2026-96660 · CVE Program
- CVE-2026-96660 · NVD
- FIRST EPSS
- GHSA-mc7j-c3xf-rrxf · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences