CVE-2026-59823: medium-severity vulnerability in BerriAI litellm
LiteLLM: Server-side request forgery via the `user_config` request parameter in LiteLLM Proxy
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.4%
LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.83.9, an authenticated LiteLLM Proxy caller with a valid virtual key can place api_base inside the user_config request body to bypass is_request_body_safe, which blocks top-level api_base and base_url but previously did not inspect or reject user_config. Because user_config constructs the outbound router, the nested destination redirects a server-side request to an internal or external host selected by the caller and can expose endpoints the caller cannot otherwise access. This issue is fixed in version 1.83.9.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N
Affected products
BerriAI · litellmRelated CVEs — BerriAI litellm
In the same product, most dangerous first.
CVE-2026-42271HIGHLiteLLM: Authenticated command execution via MCP stdio test endpointsEPSS 91.4%KEVCVE-2026-42208CRITICALLiteLLM: SQL injection in Proxy API key verificationEPSS 89.4%KEVCVE-2026-59822HIGHLiteLLM: MCP Authentication Bypass via OAuth2 Passthrough FallbackEPSS 0.8%KEVCVE-2026-35029HIGHLiteLLM affected by privilege escalation via unrestricted proxy configuration endpointEPSS 38.6%CVE-2026-49468CRITICALLiteLLM: Authentication Bypass via Host Header InjectionEPSS 3.0%CVE-2026-47101HIGHLiteLLM < 1.83.14 Privilege Escalation via API Key GenerationEPSS 1.2%