FKIE_CVE-2026-16442

Vulnerability from fkie_nvd - Published: 2026-08-05 16:16 - Updated: 2026-08-10 19:21
Severity
7.4 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
A flaw was found in the SAML broker component of Keycloak, which is used to manage identity federation and user authentication. The issue occurs because the IdP-initiated Single Sign-On endpoint fails to check if a provider is restricted to account linking only. This allows an attacker with control over a linked upstream identity to bypass login restrictions and gain full access to a local user account.
References
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:50846Vendor Advisory
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:50847Vendor Advisory
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:50848Vendor Advisory
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:50849Vendor Advisory
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-16442Vendor Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2503138Issue Tracking, Vendor Advisory
Impacted products
Vendor Product Version
redhat build_of_keycloak *
redhat build_of_keycloak *
To clipboard 

{
  "affected": [
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          "packageName": "keycloak-services",
          "product": "Red Hat Single Sign-On 7",
          "vendor": "Red Hat"
        }
      ],
      "source": "secalert@redhat.com"
    }
  ],
  "configurations": [
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  "cveTags": [],
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    }
  ],
  "id": "CVE-2026-16442",
  "lastModified": "2026-08-10T19:21:47.070",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
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        "type": "Secondary"
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            {
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            {
              "technicalImpact": "partial"
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          "role": "CISA Coordinator",
          "timestamp": "2026-08-05T15:40:39.570480Z",
          "version": "2.0.3"
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      "source": "secalert@redhat.com",
      "type": "Secondary"
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}



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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

Author Source Type Date Other

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.
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  • 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.