{"id":"CVE-2026-59823","aliases":["GHSA-hx8v-g79f-8w5f"],"url":"https://o3.security/vulnerability/CVE-2026-59823","summary":"LiteLLM: Server-side request forgery via the `user_config` request parameter in LiteLLM Proxy","details":"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.","published":"2026-09-16T18:36:21.105Z","modified":"2026-09-18T03:49:16.305492527Z","cvss":null,"epss":{"score":0.00439,"percentile":0.37429,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"litellm","fixedVersion":"1.83.9"}],"fix":{"url":"https://github.com/BerriAI/litellm/commit/47214be317f45a2d2ac08258362e0481411eb427","label":"BerriAI/litellm@47214be"},"references":[{"type":"ADVISORY","url":"https://github.com/BerriAI/litellm/security/advisories/GHSA-hx8v-g79f-8w5f"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59823.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59823"},{"type":"FIX","url":"https://github.com/BerriAI/litellm/commit/47214be317f45a2d2ac08258362e0481411eb427"},{"type":"FIX","url":"https://github.com/BerriAI/litellm/pull/25827"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-18T03:49:16.305492527Z"}}