The User Registration & Membership plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `embed_form_action()` function in all versions up to, and including, 5.1.4. This makes it possible for authenticated attackers, with Contributor-level access and above, to append shortcode content to arbitrary pages they do not own or have permission to edit.
CVE-2026-3601 is a medium severity with CVSS 4.3 Vulnerability issue affecting the Plugin User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder. It affects Versions up to 5.1.4 and is fixed in 5.1.5.
Use the related hub and response guides to connect this CVE-2026-3601 report with patch validation, scanner checks, and site hardening work.
Open the grouped hub for related CVEs, affected ranges, severity mix, and patch coverage.
Check access, XML-RPC exposure, backup readiness, and monitoring after patching.
Use containment, evidence capture, remediation, and validation steps when exploit risk is high.
CVE-2026-3601 is tracked for the Plugin User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder as medium severity with CVSS 4.3. The affected range is Versions up to 5.1.4. Update User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder to 5.1.5 or newer where that version is compatible with the site.
Search engines and operators need more than a title. This page exposes the identifier, affected range, patch evidence, and source coverage that make the vulnerability actionable.
This report has a CVE identifier, which makes it suitable for focused search and vulnerability triage workflows.
Affected version data gives operators a concrete comparison point against installed WordPress software.
A fixed version is present, so the page can answer update and remediation intent directly.
External references are available for source validation, advisory review, and incident notes.
Use these checks when converting this record into a patch ticket, incident note, or risk acceptance decision.
Inventory the installed Plugin package and compare its version with Versions up to 5.1.4.
Confirm User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder is updated to 5.1.5 or newer.
Review references and CVSS vector details for exploitability, authentication requirements, and exposure path.
After patching, re-run vulnerability monitoring and keep the related plugin or theme hub under review for follow-up CVEs.
| Software Type | Plugin |
|---|---|
| Software Slug |
user-registration
View on wordpress.org
|
| CVE | CVE-2026-3601 |
| Patched Versions |
5.1.5
|
| Affected Versions |
Versions up to 5.1.4
|
These internal links group the same WordPress plugin by CVE, issue type, severity, and patch status so operators and search engines can connect the full vulnerability cluster.
User Registration <= 3.0.2 - Authenticated (Subscriber+) Arbitrary File Upload
User Registration & Membership <= 5.1.2 - Unauthenticated Privilege Escalation via Membership Registration
User Registration & Membership <= 4.1.1 - Unauthenticated Privilege Escalation
User Registration – Custom Registration Form, Login Form, and User Profile WordPress Plugin <= 3.1.5 - Missing Authorization to Authenticated (Subscriber+) Privilege Escalation
User Registration <= 3.0.1 - Authenticated (Subscriber+) PHP Object Injection
User Registration <= 2.2.4 - Authenticated (Subscriber+) Arbitrary File Upload
User Registration & Membership <= 5.1.2 - Authentication Bypass
User Registration & Membership <= 4.1.2 - Authentication Bypass
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