Cyber Resilience

CVE-2026-4630

Access Control in Redhat Build Of Keycloak 26.4 – 26.4.12

Published
19 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 6.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0030 23th percentile
Risk Priority 42 floored blend · peak EPSS

Summary

CVE-2026-4630 is a medium-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Redhat Build Of Keycloak. Its CVSS base score is 6.8 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 23th 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 client could exploit an Insecure Direct Object Reference (IDOR) vulnerability in the Authorization Services Protection API endpoint. By knowing or obtaining a resource's unique identifier (UUID) belonging to another Resource Server within…

more

the same realm, the client could bypass authorization checks. This allows the client to perform unauthorized GET, PUT, and DELETE operations on resources, leading to information disclosure and potential unauthorized modification or deletion of data.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

IDOR authz bypass in exposed Keycloak Protection API directly enables exploitation of a public-facing application for unauthorized data access/modification.

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

CVEs Like This One

CVE-2026-9087Same product: Redhat Build Of Keycloak
CVE-2026-37978Same product: Redhat Build Of Keycloak
CVE-2026-4628Same product: Redhat Build Of Keycloak
CVE-2026-9792Same product: Redhat Build Of Keycloak
CVE-2026-9689Same product: Redhat Build Of Keycloak
CVE-2026-37977Same product: Redhat Build Of Keycloak
CVE-2026-9099Same product: Redhat Build Of Keycloak
CVE-2026-9799Same product: Redhat Build Of Keycloak
CVE-2026-7500Same product: Redhat Build Of Keycloak
CVE-2026-37979Same product: Redhat Build Of Keycloak

Affected Assets

redhat
build of keycloak
26.4 — 26.4.12

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-4 Information Flow Enforcement
  • SI-10 Information Input Validation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authorization policy on resource UUIDs so an authenticated client cannot perform GET/PUT/DELETE on another Resource Server's objects.

prevent

Enforces information-flow rules between realms and resource servers, blocking unauthorized cross-resource access via direct object references.

prevent

Validates that supplied resource identifiers are authorized for the requesting client before any Authorization Services API operation.

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 full match
prevents

Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.

PR.IR-01 mostly match
prevents

Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.

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.

detects

Security testing can detect missing authorization checks but does not prevent the weakness in production.

prevents

Information access restriction explicitly enforces that users may only retrieve data they are authorized to see, directly addressing user-controlled key bypass.

prevents

Access control policy directly requires enforcement of authorization rules that prevent unauthorized access via manipulated keys.

prevents

Managing access rights includes ensuring users can only access their own records and not bypass authorization by altering identifiers.

mitigates

Privileged access rights control restricts what data each user may access, mitigating direct object reference attacks.

prevents

Secure development lifecycle includes authorization design but does not itself implement runtime access checks.

References