Detections
Analytics

CVE-2026-59823

medium

Description

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.

References

https://www.infosecurity-magazine.com/news/high-risk-vulnerabilities-llm-tool/

https://www.itsecurityguru.org/2026/10/13/litellm-flaws-let-low-privileged-users-hijack-ai-gateway-and-steal-provider-keys/?utm_source=rss&utm_medium=rss&utm_campaign=litellm-flaws-let-low-privileged-users-hijack-ai-gateway-and-steal-provider-keys

https://research.checkpoint.com/2026/when-llm-gateways-go-wrong-findings-from-litellm/

https://blog.checkpoint.com/security/check-point-research-discovers-high-risk-vulnerabilities-in-litellm-one-of-the-most-widely-used-llm-gateways/

https://github.com/BerriAI/litellm/security/advisories/GHSA-hx8v-g79f-8w5f

https://github.com/BerriAI/litellm/pull/25827

https://github.com/BerriAI/litellm/commit/47214be317f45a2d2ac08258362e0481411eb427

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-80986

Details

Source: Mitre, NVD

Published: 2026-09-16

Updated: 2026-09-30

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 9.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

CVSS v4

Base Score: 5.3

Vector: 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

Severity: Medium

EPSS

EPSS: 0.00439