CVE-2026-27478CWE-1390CWE-290CWE-346

Unity Catalog has a JWT Issuer Validation Bypass Allows Complete User Impersonation

Critical · published March 11, 2026

CVSS v3.1
9.1
EPSS
0%
Percentile
14.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00239 · 14.2th percentile
Weaknesses
CWE-1390 · Weak Authentication; CWE-290 · Authentication Bypass by Spoofing; CWE-346 · Origin Validation Error
Published
2026-03-11T19:36Z
EPSS history
Timeline
  • 11 MAR 19:36Z
    Unity Catalog has a JWT Issuer Validation Bypass Allows Complete User Impersonation
    cvelistv5