Research · Jul 8, 2026 · ZeroDay Catalog
Improper Authentication Vulnerability in BerriAI LiteLLM
BerriAI has addressed an improper authentication vulnerability in LiteLLM that could allow unauthorized access to its MCP tooling.
What changed
BerriAI has released version 1.84.0 of LiteLLM, which resolves an improper authentication vulnerability. This flaw allowed unauthenticated attackers to bypass key validation by exploiting the MCP Streamable HTTP endpoint.
The vulnerability enabled attackers to use a forged Authorization header to trigger a fallback mechanism that could grant access without a valid LiteLLM key.
Who is affected
Organizations utilizing BerriAI's LiteLLM prior to version 1.84.0 are at risk of unauthorized access to sensitive MCP tooling.
This vulnerability primarily impacts developers and businesses leveraging LiteLLM as a proxy server for LLM API calls.
- BerriAI LiteLLM users prior to version 1.84.0
- Companies integrating LiteLLM into their AI workflows
- Developers relying on LiteLLM for API access
What to do
It is crucial for affected users to upgrade to LiteLLM version 1.84.0 or later to mitigate the risk associated with this vulnerability.
Additionally, organizations should review their authentication mechanisms and consider implementing additional security measures to prevent unauthorized access.
- Upgrade LiteLLM to version 1.84.0 immediately
- Audit existing API access controls
- Implement enhanced logging and monitoring for API calls