ZITADEL 3.0.0 before 4.19.2 Account Takeover via SAML Identity-Provider Confusion
Published Oct 12, 2026 · Updated Oct 23, 2026
Original summary
Normalized public record · Updated Oct 23, 2026
ZITADEL 3.0.0 before 4.19.2 Account Takeover via SAML Identity-Provider Confusion
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
ZITADEL 4.x before 4.19.2 and 3.x through 3.4.15 contains an authentication bypass in the SAML identity-provider intent callback, which verifies the assertion signature using the provider named in the request URL but resolves the user from the login intent without checking they match. Attackers with organization-administrator permission can register a SAML provider with their own signing key to obtain authenticated sessions as any user linked to another SAML provider on the instance, including in other organizations.
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
- 10%
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
- Security advisory ↗
- VulnCheck Advisory: ZITADEL 3.0.0 before 4.19.2 Account Takeover via SAML Identity-Provider Confusion ↗
Record history
Published Oct 12, 2026 · Last refreshed Oct 23, 2026