Description
LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. From 1.87.0 until 1.100.4, 1.101.3, 1.102.2, 1.103.1, and 1.104.0-rc.2, the proxy reuses one cryptographic context for at-rest secrets and session tokens, allowing an authenticated internal user to have crafted metadata containing a forged administrator credential encrypted and returned by the API-key flow. Replaying that ciphertext as a bearer token causes the proxy to trust the forged proxy administrator identity, permitting administrative access and arbitrary commands through the MCP stdio endpoint. Versions 1.87.0 through 1.90.x require EXPERIMENTAL_UI_LOGIN to be enabled, while versions after 1.91.0 are exploitable in the default configuration. This issue was fixed in LiteLLM 1.100.4, 1.101.3, 1.102.2, 1.103.1, and 1.104.0-rc.2.
References10
- github.com/BerriAI/litellm/commit/1d5fdc87fed66b49e1df8cf7d708a…
- github.com/BerriAI/litellm/commit/9161d7f9d6073603ba61ee4aa5e2c…
- github.com/BerriAI/litellm/commit/9fa1a641119dd0d4fe43e93622eae…
- github.com/BerriAI/litellm/commit/a80eacacee118fbed54e3d98f239d…
- github.com/BerriAI/litellm/commit/f7cd90f09e9716652b38daec9f064…
- github.com/BerriAI/litellm/releases/tag/v1.100.4
- github.com/BerriAI/litellm/releases/tag/v1.101.3
- github.com/BerriAI/litellm/releases/tag/v1.102.2
- github.com/BerriAI/litellm/releases/tag/v1.103.1
- github.com/BerriAI/litellm/releases/tag/v1.104.0-rc.2
Metrics
- CVSS 3.1
-
9.9
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 8 November 2026
- CWE
- CWE-269CWE-345CWE-441
Could this be exploited in your environment?
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