{"id":"CVE-2026-55641","aliases":["GHSA-86m2-fcxq-5q7c"],"url":"https://o3.security/vulnerability/CVE-2026-55641","summary":"9router: Unauthenticated `/v1` proxy access via `Host`-header spoofing → open AI relay + SSRF","details":"9Router is an AI router & token saver. Prior to 0.5.2, 9router determines whether a /v1 LLM proxy request is local by reading the client-controlled Host header, allowing a remote unauthenticated attacker to send Host: localhost and bypass API-key authentication. In the default configuration, this exposes the /v1 proxy to upstream provider calls using stored provider credentials and allows /v1/search with the searxng provider_options.baseUrl parameter to drive server-side requests to internal or cloud-metadata hosts. This issue is fixed in version 0.5.2.","published":"2026-07-10T15:36:05.964Z","modified":"2026-08-12T03:51:12.348487734Z","cvss":{"score":8.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N"},"epss":{"score":0.00323,"percentile":0.24598,"asOf":"2026-08-28"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"9router","fixedVersion":"0.5.2"}],"fix":{"url":"https://github.com/decolua/9router/commit/b282f0554972ea35281520738759d76abcd0b0b3","label":"decolua/9router@b282f05"},"references":[{"type":"WEB","url":"https://github.com/decolua/9router/releases/tag/v0.5.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55641.json"},{"type":"ADVISORY","url":"https://github.com/decolua/9router/security/advisories/GHSA-86m2-fcxq-5q7c"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55641"},{"type":"FIX","url":"https://github.com/decolua/9router/commit/b282f0554972ea35281520738759d76abcd0b0b3"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:12.348487734Z"}}