{"cve":"CVE-2026-54238","nvd":{"published":"2026-10-22T18:17:28.993","modified":"2026-10-23T19:42:24.553","status":"Awaiting Analysis","description":"Supabase Realtime provides Broadcast, Presence, and Postgres Changes via WebSockets. Prior to version 2.103.1, the REST broadcast endpoints accept an expired JWT when the exp claim is encoded as a JSON string instead of a JSON number. The same route rejects an expired integer exp token signed with the same tenant secret. The accepted request returns 202 and emits the broadcast to subscribers. This could allow an unauthenticated attacker can broadcast realtime messages to subscribers. The attack can be performed via the Internet/only from within the supabase project. The impact of broadcasting messages to subscribers is application specific. This issue has been patched in version 2.103.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","score":3.1},"cwes":["CWE-613"],"references":["https://github.com/supabase/realtime/commit/ac229d7eff2798b12b994e07bdd64f5e9b56374a","https://github.com/supabase/realtime/pull/1934","https://github.com/supabase/realtime/releases/tag/v2.103.1","https://github.com/supabase/realtime/security/advisories/GHSA-hg9h-6mhq-6c2v"],"products":[],"source":"nvd","synced_at":"2026-10-24T16:53:35.584907681+00:00"},"epss":{"cve":"CVE-2026-54238","score":0.00206,"percentile":0.10635,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}