pac4j-oidc before 6.5.6 Privilege Escalation via Unverified Keycloak Access Token
Published Aug 29, 2026 · Updated Nov 3, 2026
Original summary
Normalized public record · Updated Nov 3, 2026
pac4j-oidc before 6.5.6 Privilege Escalation via Unverified Keycloak Access Token
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
pac4j-oidc before 6.5.6 fails to verify access token signatures, issuers, audiences, or expiry when extracting Keycloak realm and client roles. Attackers can forge access tokens with administrative roles paired with valid ID tokens to bypass authorization checks in applications relying on pac4j role validation.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- MEDIUM
- Confidence
- Not available
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
- Patch commit ↗
- pac4j Security Advisory for pac4j-core, pac4j-oidc and pac4j-saml ↗
- Source repository ↗
- Source repository ↗
- VulnCheck Advisory: pac4j-oidc before 6.5.6 Privilege Escalation via Unverified Keycloak Access Token ↗
Record history
Published Aug 29, 2026 · Last refreshed Nov 3, 2026