RHSA-2026:56520

Vulnerability from csaf_redhat - Published: 2026-08-18 20:36 - Updated: 2026-10-23 16:40
Summary
Red Hat Security Advisory: Red Hat build of Keycloak 26.4.15 Security Update
Severity
Critical
Notes
Topic: New Red Hat build of Keycloak 26.4.15 packages are available from the Customer Portal
Details: Red Hat build of Keycloak 26.4.15 is a standalone server, based on the Keycloak project, that provides authentication and standards-based single sign-on capabilities for web and mobile applications. Security fixes: * Unauthenticated account takeover via reset-credentials flow bypass (CVE-2026-18963)
Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.
CVE-2026-18963

A flaw was found in the reset-credentials flow of the keycloak-services component, which is the core engine for identity and access management in Red Hat Build of Keycloak. The issue allows an unauthenticated attacker to force the password reset process for any user without needing to click the required email verification link. This can result in the attacker gaining full control over target user accounts by directly setting new credentials.

9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE-640 - Weak Password Recovery Mechanism for Forgotten Password
Affected products
Product Identifier Version Remediation
Red Hat build of Keycloak 26.4.15
Red Hat / Red Hat build of Keycloak
 cpe:/a:redhat:build_keycloak:26.4 —
Vendor Fix fix
Workaround
Threats
Impact Critical
CVE-2026-54291

A flaw was found in pgjdbc, an open-source PostgreSQL JDBC Driver. A remote attacker who can intercept a TLS (Transport Layer Security) connection can silently downgrade connections configured to require channel binding from SCRAM-SHA-256-PLUS to plain SCRAM-SHA-256. This downgrade bypasses the intended man-in-the-middle protection, allowing the attacker to potentially intercept or alter sensitive communication. The vulnerability occurs because the system fails to properly validate the channel binding when a specific type of certificate is used.

5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE-940 - Improper Verification of Source of a Communication Channel
Affected products
Fixed 1 product, the same list as for CVE-2026-18963
Threats
Impact Moderate
References
Acknowledgments
James Paremain
To clipboard 

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        "text": "New Red Hat build of Keycloak 26.4.15 packages are available from the Customer Portal",
        "title": "Topic"
      },
      {
        "category": "general",
        "text": "Red Hat build of Keycloak 26.4.15 is a standalone server, based on\nthe Keycloak project, that provides authentication and\nstandards-based single sign-on capabilities for web and mobile\napplications.\n\nSecurity fixes:\n* Unauthenticated account takeover via reset-credentials flow bypass (CVE-2026-18963)",
        "title": "Details"
      },
      {
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        "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.",
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        {
          "category": "description",
          "text": "A flaw was found in the reset-credentials flow of the keycloak-services component, which is the core engine for identity and access management in Red Hat Build of Keycloak. The issue allows an unauthenticated attacker to force the password reset process for any user without needing to click the required email verification link. This can result in the attacker gaining full control over target user accounts by directly setting new credentials.",
          "title": "Vulnerability description"
        },
        {
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          "title": "Vulnerability summary"
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          "category": "other",
          "text": "The Red Hat Product Security team has assessed the severity of this vulnerability as Critical, given that it can be exploited by an unauthenticated remote attacker without any user interaction. Successful exploitation allows an attacker to gain full access to any user account by bypassing the email verification step in the password recovery process. The vulnerability\u0027s root cause is improper state validation within the reset-credentials authentication flow.",
          "title": "Statement"
        },
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          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product\u0027s status, and are included for informational purposes to better understand the severity of this vulnerability.",
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        },
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        }
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      "release_date": "2026-08-17T00:00:00+00:00",
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          "date": "2026-08-18T20:36:54+00:00",
          "details": "Before applying the update, back up your existing installation,\nincluding all applications, configuration files, databases and\ndatabase settings, and so on.",
          "product_ids": [
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          ],
          "restart_required": {
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        },
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          "category": "workaround",
          "details": "If an immediate upgrade is not possible, disabling the \"Forgot password\" functionality across all realms can be used as a temporary mitigation.\n\nIn the RHBK administration console, navigate to:\n\nRealm settings \u2192 Login \u2192 Forgot password \u2192 Off\n\nApply this setting to all realms.\n\nUpgrade to a fixed version as soon as possible.",
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          "title": "Vulnerability description"
        },
        {
          "category": "summary",
          "text": "org.postgresql/postgresql: com.ongres.scram/scram-client: pgjdbc: Man-in-the-middle protection bypass via SCRAM-SHA-256-PLUS downgrade",
          "title": "Vulnerability summary"
        },
        {
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        {
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          "summary": "https://github.com/pgjdbc/pgjdbc/commit/77df98e4e66c12936ded3478a0954f6f580bad99",
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            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
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        }
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        {
          "category": "impact",
          "details": "Moderate"
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      ],
      "title": "org.postgresql/postgresql: com.ongres.scram/scram-client: pgjdbc: Man-in-the-middle protection bypass via SCRAM-SHA-256-PLUS downgrade"
    }
  ]
}



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