Keycloak vulnerable to user impersonation via stolen UUID code (CVE-2023-0264) | HOL Guard CVE

High · CVSS 8.7CVE-2023-0264GHSA-9G98-5MJ6-F9MV

Keycloak vulnerable to user impersonation via stolen UUID code

Answer in brief

CVE-2023-0264 records a High severity (CVSS 8.7) vulnerability in Keycloak vulnerable to user impersonation via stolen UUID code. The current sources do not mark it as known exploited. The current feed maps org.keycloak:keycloak-services (maven). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Mar 2, 2023Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Sep 10, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.7
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps org.keycloak:keycloak-services (maven). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
org.keycloak:keycloak-servicesmaven	>=0 <21.0.1	21.0.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for org.keycloak:keycloak-services.
Review the reported fix. Update org.keycloak:keycloak-services to 21.0.1 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Mar 2, 2023
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Sep 10, 2026

Sources and claim methodology

Upstream source description

Keycloak's OpenID Connect user authentication was found to incorrectly authenticate requests. An authenticated attacker who could also obtain a certain piece of info from a user request, from a victim within the same realm, could use that data to impersonate the victim and generate new session tokens.

Quoted source text, attributed separately from HOL analysis.