What changed

LiteLLM patched an authentication bypass where an unauthenticated token sharing a cached prefix could inherit another user's identity and permissions in JWT or OIDC deployments using user-info caching.

Why it matters

An AI gateway centralizes provider credentials, quotas, and access decisions, so an identity cache collision can expose models, data, budgets, and administrative actions across tenants.

What to do

Upgrade to 1.83.0 or later, invalidate sessions, review cache settings, set the user-info cache TTL to zero if delayed, and audit unusual identities and requests.

Caveat

JWT authentication and user-info caching are not enabled by default, exposure depends on configuration, and the advisory does not prove any particular gateway was exploited.