dbcve.org
Missing AuthorizationWeakness · CWE-862

CVE-2026-4056

MEDIUM · 5.4 CVSS v3.1 Published 2026-03-24
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
60/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The User Registration & Membership plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the Content Access Rules REST API endpoints in versions 5.0.1 through 5.1.4. This is due to the `check_permissions()` method only checking for `edit_posts` capability instead of an administrator-level capability. This makes it possible for authenticated attackers, with Contributor-level access and above, to list, create, modify, toggle, duplicate, and delete site-wide content restriction rules, potentially exposing restricted content or denying legitimate user access.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The User Registration & Membership plugin for WordPress has a broken access control vulnerability in its Content Access Rules REST API endpoints. The check_permissions() method only verifies the edit_posts capability (available to Contributors), rather than requiring administrator-level privileges. This allows any authenticated user with Contributor-level access or higher to modify site-wide content restriction rules.

MitigationUpdate the plugin to version 5.1.5 or later which implements proper administrator-level capability checks on Content Access Rules REST API endpoints.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check if User Registration & Membership plugin is installed
    In WordPress admin, go to Plugins > Installed Plugins and look for 'User Registration & Membership' or 'User Registration' plugin. Alternatively, check the plugins directory at /wp-content/plugins/ for a folder containing 'user-registration'
    Affected if Plugin is not installed - not affected
  2. Identify the installed plugin version
    In Plugins > Installed Plugins, click on the plugin to view details and note the version number. Alternatively, check the main plugin PHP file header for 'Version:' field
    Affected if Version is before 5.1.5 - likely affected; version 5.1.5 or later - not affected by this specific vulnerability
  3. Verify Content Access Rules feature is enabled
    Check WordPress admin for User Registration settings. Look for Content Access, Content Restriction, or Membership settings under the User Registration plugin menu. Inspect whether any content restriction rules have been configured under the Content Access Rules section
    Affected if No content restriction rules configured - limited exposure; content restriction rules exist - full exposure to the vulnerability
  4. Review user roles with Contributor-level access
    In WordPress admin, go to Users > All Users and review which users have Contributor, Author, Editor, or custom roles. Any of these roles can exploit this vulnerability if the plugin is vulnerable
    Affected if No users with Contributor or higher roles exist - lower risk; users with Contributor/Author/Editor roles present - potential for exploitation

The environment is affected if the User Registration & Membership plugin version is before 5.1.5 AND the Content Access Rules feature is enabled or configured with restriction rules.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update the plugin to version 5.1.5 or later which implements proper administrator-level capability checks on Content Access Rules REST API endpoints.

Recommended fix Moderate confidence

Version 5.1.5 or later (any version after 5.1.4)

  1. Log in to the WordPress admin dashboard
  2. Navigate to Plugins > Installed Plugins
  3. Locate the 'User Registration & Membership' plugin
  4. Check the current version number to confirm it is between 5.0.1 and 5.1.4
  5. Click 'Update Now' if an update is available, or manually download the latest version from wordpress.org/plugins/user-registration
  6. After updating, verify the new version number in the plugins list
  7. Test that content restriction rules can only be modified by administrators

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation1.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
5.0 hours of engineering $860
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-4056 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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