Out-of-bounds Read Affecting keycloak-advanced-compat package, versions <26.6.3-r0


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.42% (34th percentile)

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  • Snyk IDSNYK-MINIMOSLATEST-KEYCLOAKADVANCEDCOMPAT-17805455
  • published3 Jul 2026
  • disclosed28 May 2026

Introduced: 28 May 2026

CVE-2026-9803  (opens in a new tab)
CWE-125  (opens in a new tab)

How to fix?

Upgrade Minimos:latest keycloak-advanced-compat to version 26.6.3-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream keycloak-advanced-compat package and not the keycloak-advanced-compat package as distributed by Minimos. See How to fix? for Minimos:latest relevant fixed versions and status.

A flaw was found in Keycloak's ClientRegistrationAuth component. A remote unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with a malformed 'Authorization: Bearer' header to any client registration endpoint. This can lead to an ArrayIndexOutOfBoundsException, causing the server to return an HTTP 500 error and resulting in a Denial of Service (DoS) for the affected service.

CVSS Base Scores

version 3.1