dbcve.org
Open RedirectWeakness · CWE-601

CVE-2026-6203

MEDIUM · 6.1 CVSS v3.1 Published 2026-04-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges

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 Open Redirect in versions up to and including 5.1.4. This is due to insufficient validation of user-supplied URLs passed via the 'redirect_to_on_logout' GET parameter before redirecting users. The `redirect_to_on_logout` GET parameter is passed directly to WordPress's `wp_redirect()` function instead of the domain-restricted `wp_safe_redirect()`. While `esc_url_raw()` is applied to sanitize malformed URLs, it does not restrict the redirect destination to the local domain, allowing an attacker to craft a specially formed link that redirects users to potentially malicious external URLs after logout, which could be used to facilitate phishing attacks.

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 WordPress plugin uses wp_redirect() with the redirect_to_on_logout parameter instead of wp_safe_redirect(). While esc_url_raw() sanitizes malformed URLs, it doesn't restrict redirects to the local domain, allowing open redirect to external malicious URLs.

MitigationUpdate the plugin beyond version 5.1.4 once a fix is released. Alternatively, add domain validation or use wp_safe_redirect() with allowed domains before the redirect call.

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
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/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. Confirm the plugin is installed
    Check if the 'User Registration & Membership' plugin exists in your WordPress installation under wp-content/plugins/ or view it in the WordPress admin Plugins page
    Affected if The plugin is installed and active
  2. Identify the installed version
    Open the main plugin file (usually user-registration.php) and locate the version constant or header, or check the plugin row in WordPress admin Plugins list
    Affected if The installed version is 5.1.4 or lower (the fix is expected in versions above 5.1.4)
  3. Check if logout redirect is configured
    Navigate to User Registration plugin settings in WordPress admin, look for logout-related settings or the redirect_to_on_logout parameter configuration
    Affected if The redirect_to_on_logout feature is enabled or configured
  4. Inspect the redirect handler code
    Examine the plugin files for calls to wp_redirect() using the redirect_to_on_logout parameter (typically in logout functions). Check if esc_url_raw() is used without domain validation
    Affected if The code uses wp_redirect() with redirect_to_on_logout and esc_url_raw() without validating the URL points to the local domain

You are affected if the plugin is installed, the version is 5.1.4 or lower, and the logout redirect feature using redirect_to_on_logout is enabled, allowing arbitrary external URLs to be used as redirect targets.

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 beyond version 5.1.4 once a fix is released. Alternatively, add domain validation or use wp_safe_redirect() with allowed domains before the redirect call.

Recommended fix Moderate confidence

User Registration & Membership plugin version 5.1.5 or latest available version

  1. Backup your WordPress site before making any changes
  2. Update the 'User Registration & Membership' plugin to the latest available version (5.1.5 or later)
  3. After updating, verify the logout redirect functionality works correctly by testing with a valid internal URL
  4. Confirm the fix prevents redirects to external domains by attempting a logout with an external URL in the redirect_to_on_logout parameter - it should be blocked or sanitized

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

Have this fixed Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
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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-2026-6203 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data