What’s Vulnerable › Vulnerabilities

CVE-2026-6203: User Registration & Membership <= 5.1.4 - Unauthenticated Open Redirect via 'redirect_to_on_logout' Parameter

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-13 · updated 2026-06-17
• Weakness: CWE-601

Description

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.

Affected products

• wpeverest User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Cu: through 5.1.4

References

• https://plugins.trac.wordpress.org/browser/user-registration/tags/5.1.4/includes/functions-ur-template.php#L39
• https://plugins.trac.wordpress.org/browser/user-registration/trunk/includes/functions-ur-template.php#L39
• https://www.wordfence.com/threat-intel/vulnerabilities/id/020bed37-9544-49b7-941d-3b7f509fdfdf?source=cve

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