CVE-2026-3872 (GCVE-0-2026-3872)

Vulnerability from cvelistv5 – Published: 2026-04-02 12:37 – Updated: 2026-04-02 16:34
VLAI?
Title
Keycloak: keycloak: information disclosure due to redirect_uri validation bypass
Summary
A flaw was found in Keycloak. This issue allows an attacker, who controls another path on the same web server, to bypass the allowed path in redirect Uniform Resource Identifiers (URIs) that use a wildcard. A successful attack may lead to the theft of an access token, resulting in information disclosure.
Severity ?
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CWE
  • CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
Assigner
References
https://access.redhat.com/errata/RHSA-2026:6475 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6476 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6477 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6478 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-3872 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2445988 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat build of Keycloak 26.2 Unaffected: 26.2.15-1 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.2::el9
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    Red Hat Red Hat build of Keycloak 26.2 Unaffected: 26.2-18 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.2::el9
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    Red Hat Red Hat build of Keycloak 26.2 Unaffected: 26.2-18 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.2::el9
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    Red Hat Red Hat build of Keycloak 26.2.15     cpe:/a:redhat:build_keycloak:26.2::el9
 Create a notification for this product.
    Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4.11-1 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
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    Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-14 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
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    Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-14 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
 Create a notification for this product.
    Red Hat Red Hat build of Keycloak 26.4.11     cpe:/a:redhat:build_keycloak:26.4::el9
 Create a notification for this product.
Date Public ?
2026-04-02 12:30
Show details on NVD website
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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.



Detection rules are retrieved from Rulezet.