Cyber Resilience

CVE-2026-9791

Access Control in Redhat Build Of Keycloak

Published
28 May 2026
Modified
26 June 2026
Patch / advisory
CVSS Score v3.1 4.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0022 12th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-9791 is a medium-severity Incorrect Authorization (CWE-863) vulnerability in Redhat Build Of Keycloak. Its CVSS base score is 4.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Domain Groups (T1069.002); ranked at the 12th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A flaw was found in Keycloak. An authenticated user with existing organization membership can exploit this flaw by accessing user-facing APIs, such as the account API or by requesting an OpenID Connect (OIDC) token with the 'organization' scope. This allows…

more

organization metadata to be disclosed in tokens, even after an administrator has explicitly disabled the Organizations feature, potentially leading to incorrect authorization decisions by resource servers.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1069.002 Domain Groups Discovery
Adversaries may attempt to find domain-level groups and permission settings.
T1087.002 Domain Account Discovery
Adversaries may attempt to get a listing of domain accounts.
Why these techniques?

Vulnerability enables unauthorized disclosure of organization metadata (treated as domain/permission group info) via APIs and tokens despite explicit disablement, directly facilitating group and account discovery.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1087 Account Discovery Discoveryconfidence: HIGH
The flaw enables unauthorized disclosure of organization metadata via user-facing APIs and OIDC tokens, directly facilitating account discovery.
T1526 Cloud Service Discovery Discoveryconfidence: HIGH
Bypassing the disabled Organizations feature to obtain organization metadata in tokens enables cloud service discovery.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-9793Same product: Redhat Build Of Keycloak
CVE-2026-4628Same product: Redhat Build Of Keycloak
CVE-2026-9796Same product: Redhat Build Of Keycloak
CVE-2026-9792Same product: Redhat Build Of Keycloak
CVE-2026-12388Same product: Redhat Build Of Keycloak
CVE-2026-8922Same product: Redhat Build Of Keycloak
CVE-2026-4629Same product: Redhat Build Of Keycloak
CVE-2026-9794Same product: Redhat Build Of Keycloak
CVE-2025-3910Same product: Redhat Build Of Keycloak
CVE-2026-2575Same product: Redhat Build Of Keycloak

Affected Assets

redhat
build of keycloak
all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-4 Information Flow Enforcement
  • CM-6 Configuration Settings
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authorization decisions so that organization metadata is not returned via APIs or OIDC tokens once the Organizations feature has been disabled.

prevent

Controls information flows in tokens and API responses to ensure organization-scoped claims are suppressed after administrative disablement.

prevent

Ensures the Organizations feature disablement setting is correctly applied and cannot be bypassed by authenticated users requesting tokens or account data.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

prevents

By tying access rights to identity, device, location and classification, the control reduces the likelihood that an authorization decision will be based on an incorrect or bypassed policy.

References