Cyber Resilience

CVE-2026-4282

Redhat Build Of Keycloak 26.2 … 26.4.11

Published
02 April 2026
Modified
15 July 2026
Patch / advisory
CVSS Score v3.1 7.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0043 35th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-4282 is a high-severity Improper Isolation or Compartmentalization (CWE-653) vulnerability in Redhat Build Of Keycloak. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Escape to Host (T1611); ranked at the 35th 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 SC-2 (Separation of System and User Functionality) and SC-3 (Security Function Isolation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-4282 is a vulnerability in Keycloak, an open-source identity and access management solution. The issue resides in the SingleUseObjectProvider, a global key-value store that lacks proper type and namespace isolation. This flaw enables an unauthenticated attacker to forge authorization codes, which can be exploited to create access tokens with administrative capabilities, resulting in privilege escalation. The vulnerability has a CVSS v3.1 base score of 7.4 (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N) and is associated with CWE-653.

An unauthenticated attacker with network access can exploit this vulnerability, though it requires high attack complexity. By forging authorization codes due to the inadequate isolation in the SingleUseObjectProvider, the attacker can obtain admin-capable access tokens. This leads to unauthorized privilege escalation, potentially allowing full administrative control over the Keycloak instance.

Red Hat has released multiple errata addressing this vulnerability, including RHSA-2026:6475, RHSA-2026:6476, RHSA-2026:6477, and RHSA-2026:6478, which provide patches for affected Keycloak deployments. Additional details are available in the Red Hat security advisory at https://access.redhat.com/security/cve/CVE-2026-4282.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A flaw was found in Keycloak. The SingleUseObjectProvider, a global key-value store, lacks proper type and namespace isolation. This vulnerability allows an unauthenticated attacker to forge authorization codes. Successful exploitation can lead to the creation of admin-capable access tokens, resulting…

more

in privilege escalation.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1611 Escape to Host Privilege Escalation
Adversaries may break out of a container or virtualized environment to gain access to the underlying host.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
T1548.001 Setuid and Setgid Privilege Escalation
An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context.
T1055 Process Injection Stealth
Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-4325Same product: Redhat Build Of Keycloak
CVE-2025-7784Same product: Redhat Build Of Keycloak
CVE-2026-18214Same product: Redhat Build Of Keycloak
CVE-2026-16106Same product: Redhat Build Of Keycloak
CVE-2026-9791Same product: Redhat Build Of Keycloak
CVE-2026-18215Same product: Redhat Build Of Keycloak
CVE-2025-3910Same product: Redhat Build Of Keycloak
CVE-2026-12388Same product: Redhat Build Of Keycloak
CVE-2026-9795Same product: Redhat Build Of Keycloak
CVE-2026-4629Same product: Redhat Build Of Keycloak

Affected Assets

redhat
build of keycloak
26.2, 26.2.15, 26.4, 26.4.11, all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 7 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

Security function isolation is the canonical mechanism for protecting higher-privilege compartments.

Process isolation maintains separate execution domains so one process cannot affect another’s privilege level.

Explicit separation of user and management functionality implements the required compartmentalization.

System partitioning creates distinct domains that enforce isolation between differently privileged components.

Access enforcement directly requires approved authorizations to be applied to compartmentalized resources.

Information flow enforcement structurally prevents unauthorized mixing of data or functions across privilege boundaries.

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

Least-privilege policy directly enforces separation of privilege levels and access rights.

PR.IR-01 mostly match
prevents

Network and environment segmentation implements the isolation required to prevent unauthorized cross-compartment access.

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.

degrades

Segregation of duties directly enforces separation of privilege levels and functions.

prevents

Network segregation is a classic technical control for isolating different privilege domains.

prevents

Secure system architecture principles explicitly call for isolation and least-privilege boundaries.

prevents

Separation of development, test and production environments is a direct application of compartmentalization.

degrades

Access control policies establish the boundaries that isolation must enforce.

degrades

Managing access rights is the operational mechanism for compartmentalizing privileges.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-653
RHEL 9 (2 rules)
  • V-258078 RHEL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-653
  • V-272496 RHEL 9 must elevate the SELinux context when an administrator calls the sudo command. prevents CWE-653
Windows 10 (1 rule)
  • V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-653
Windows 11 (1 rule)
  • V-253269 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-653
Windows Server 2016 (1 rule)
  • V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-653

References