Vulnerability
A LiteLLM MCP authentication flaw joins CISA's KEV catalog.
CVE-2026-59822 allowed reaching MCP tools configured with a fabricated Authorization header.
After a key failed validation, the OAuth2 passthrough fallback could replace it with an empty identity.
The third exploited LiteLLM flaw listed in KEV in 2026 is fixed in 1.84.0.
The gateway holds the model providers' keys and controls agents' access to MCP servers.