{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.83.9"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "47214be317f45a2d2ac08258362e0481411eb427"
            }
          ],
          "repo": "https://github.com/berriai/litellm",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-hx8v-g79f-8w5f"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59823.json"
  },
  "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.",
  "id": "CVE-2026-59823",
  "modified": "2026-09-19T03:30:35.576416318Z",
  "published": "2026-09-16T18:36:21.105Z",
  "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"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "LiteLLM: Server-side request forgery via the `user_config` request parameter in LiteLLM Proxy"
}