Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch (CVE-2026-90997) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-90997

Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch

Answer in brief

CVE-2026-90997 records a Unknown severity vulnerability in Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch. The current sources do not mark it as known exploited. The current feed maps Keycloak/Keycloak (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

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

Published Sep 17, 2026Updated Sep 17, 2026Source checked Sep 17, 2026First seen by HOL Sep 17, 2026Material review Sep 17, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. 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 Keycloak/Keycloak (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Keycloak/Keycloakgeneric	>=26.7.0 <26.7.4	26.7.4

Recommended response

Check inventory. Check lockfiles and deployed manifests for Keycloak/Keycloak.
Review the reported fix. Update Keycloak/Keycloak to 26.7.4 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 17, 2026

Sources and claim methodology

Upstream source description

A flaw was found in Keycloak. When deployed in stateless mode with MySQL or MariaDB, a mismatch in row-count semantics between the database driver and Keycloak's application logic allows an attacker to bypass replay protection. This vulnerability enables an attacker who intercepts single-use security artifacts, such as JWT client assertions, DPoP proofs, or one-time password (TOTP) codes, to replay them. Successful exploitation grants unauthorized access to the token endpoint or login flow.

Quoted source text, attributed separately from HOL analysis.