critical9.1
CVE-2026-27478
Unity Catalog has a JWT Issuer Validation Bypass tht Allows Complete User Impersonation
Impact
Unity Catalog is an open, multi-modal Catalog for data and AI. In 0.4.0 and earlier, a critical authentication bypass vulnerability exists in the Unity Catalog token exchange endpoint (/api/1.0/unity-control/auth/tokens). The endpoint extracts the issuer (iss) claim from incoming JWTs and uses it to dynamically fetch the JWKS endpoint for signature validation without validating that the issuer is a trusted identity provider.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | io.unitycatalog:unitycatalog-server | <= 0.4.0 | 0.4.1 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Unitycatalog | Unitycatalog | through 0.4.0 |