CVE-2026-59823

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.

• CWE-918

• https://github.com/BerriAI/litellm/commit/47214be317f45a2d2ac08258362e0481411eb427
• https://github.com/BerriAI/litellm/pull/25827
• https://github.com/BerriAI/litellm/security/advisories/GHSA-hx8v-g79f-8w5f

Published

Sep 16, 2026

Last Modified

Sep 17, 2026

Status

Received

• One Click Account Takeover in GranolaHow a notification link broke out of Electron and led to a one-click account takeover.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-59818etcd is a distributed key-value store for the data of a dist…8.1
• CVE-2026-59819LiteLLM is a proxy server (AI Gateway) to call LLM APIs in O…4.9
• CVE-2026-5982A vulnerability was found in D-Link DIR-605L 2.13B01. This v…8.8
• CVE-2026-59820LiteLLM is a proxy server (AI Gateway) to call LLM APIs in O…6.5
• CVE-2026-59821LiteLLM is a proxy server (AI Gateway) to call LLM APIs in O…7.2
• CVE-2026-59822LiteLLM is a proxy server (AI Gateway) to call LLM APIs in O…8.2
• CVE-2026-59825Mastodon is a free, open-source social network server based …7.4
• CVE-2026-59826Metabase is an open-source business intelligence and embedde…9.1
• CVE-2026-59827Metabase is an open-source business intelligence and embedde…8.8
• CVE-2026-59828Discourse is an open-source discussion platform. Prior to 20…5.3
• CVE-2026-59829Discourse is an open-source discussion platform. Prior to 20…4.3
• CVE-2026-5983A vulnerability was determined in D-Link DIR-605L 2.13B01. T…8.8