{"id":"CVE-2026-61684","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-61684","generatedAt":"2026-10-28T02:19:44.077Z","title":"An unauthenticated attacker can self-sign an HS256 JWT and reach /api/invoke/userInfo to disclose cross-tenant user PII by attacker-supplied tmbId values, or /api/invoke/fileUpload to write attacker-controlled content into chat files.","description":"FastGPT is a knowledge-based AI application platform. In 4.15.0-beta4, FastGPT plugin invoke reverse-call endpoints under /api/invoke/* authenticate only by verifying a JWT signed with INVOKE_TOKEN_SECRET, which defaults to the constant string token and was not set in official deployment templates. An unauthenticated attacker can self-sign an HS256 JWT and reach /api/invoke/userInfo to disclose cross-tenant user PII by attacker-supplied tmbId values, or /api/invoke/fileUpload to write attacker-controlled content into chat files. This issue is fixed in version 4.15.0-beta5.","published":"2026-07-15T15:16:48.000Z","lastModified":"2026-10-24T21:10:00.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"4.0","score":8.8,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-798"],"affected":[],"epss":{"score":0.00386,"percentile":0.3245,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/labring/FastGPT/commit/f5f1e58b25571b7107ca49d9bf96bb2b0e0a620a","source":"security-advisories@github.com"},{"url":"https://github.com/labring/FastGPT/pull/7170","source":"security-advisories@github.com"},{"url":"https://github.com/labring/FastGPT/releases/tag/v4.15.0-beta5","source":"security-advisories@github.com"},{"url":"https://github.com/labring/FastGPT/security/advisories/GHSA-w732-rq8c-chc8","source":"security-advisories@github.com"},{"url":"https://github.com/labring/FastGPT/security/advisories/GHSA-w732-rq8c-chc8","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-61684","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}