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CVE-2026-6203 (GCVE-0-2026-6203)

Vulnerability from cvelistv5 – Published: 2026-04-13 22:25 – Updated: 2026-04-24 19:30
VLAI
Title
User Registration & Membership <= 5.1.4 - Unauthenticated Open Redirect via 'redirect_to_on_logout' Parameter
Summary
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.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-14 14:02 UTC
CWE
  • CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
Assigner
References
Impacted products
Credits
Louis Deschanel Pascal SUN Anthony Cihan
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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