Cyber Resilience

CVE-2026-9798

Auth Bypass in Redhat Build Of Keycloak

Published
28 May 2026
Modified
05 August 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:N/UI:R/S:U/C:L/I:N/A:N
EPSS Score 0.0035 28th percentile
Risk Priority 36 floored blend · peak EPSS

Summary

CVE-2026-9798 is a medium-severity Authentication Bypass by Primary Weakness (CWE-305) vulnerability in Redhat Build Of Keycloak. Its CVSS base score is 4.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 28th 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 IA-2 (Identification and Authentication (Organizational Users)) and IA-8 (Identification and Authentication (Non-organizational Users)) — 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 open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow…

more

to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

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.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-37978Same product: Redhat Build Of Keycloak
CVE-2026-7571Same product: Redhat Build Of Keycloak
CVE-2026-8830Same product: Redhat Build Of Keycloak
CVE-2026-4636Same product: Redhat Build Of Keycloak
CVE-2026-9799Same product: Redhat Build Of Keycloak
CVE-2026-9099Same product: Redhat Build Of Keycloak
CVE-2026-7307Same product: Redhat Build Of Keycloak
CVE-2026-9083Same product: Redhat Build Of Keycloak
CVE-2026-9087Same product: Redhat Build Of Keycloak
CVE-2026-3047Same product: Redhat Build Of Keycloak

Affected Assets

redhat
build of keycloak
all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.4.3
  • V7.2.4

Mitigating Controls (NIST 800-53 r5) AI

Requires unique identification and authentication of users, structurally blocking bypass of the mechanism.

Requires unique identification and authentication of non-organizational users, blocking bypass paths.

Enforces approved authorizations so a bypass weakness cannot be exploited to reach resources.

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.PS-06 full match
prevents

Secure development practices throughout the SDLC prevent the primary weaknesses that enable authentication bypass.

PR.AA-03 mostly match
prevents

Strong authentication mechanisms and policy enforcement directly reduce bypass opportunities arising from implementation flaws.

ID.RA-01 partial match
prevents

Identifying and recording vulnerabilities catches the primary weaknesses that allow authentication bypass.

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.

finds

Security testing can detect authentication bypass conditions before deployment.

prevents

Secure development lifecycle reduces likelihood of introducing bypass flaws during implementation.

prevents

Secure coding practices help prevent the primary weakness that enables authentication bypass.

mitigates

Information access restriction complements authentication by limiting what can be reached even if bypass occurs.

prevents

Secure authentication mechanisms directly address bypass risks in the implemented authentication process.

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).

Ubuntu 22.04 (1 rule)
  • V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. prevents CWE-305
Ubuntu 24.04 (1 rule)
  • V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. prevents CWE-305

References