{"cve":"CVE-2025-43855","nvd":{"published":"2025-04-24T14:15:59.483","modified":"2026-06-17T09:24:39.137","status":"Deferred","description":"tRPC allows users to build & consume fully typesafe APIs without schemas or code generation. In versions starting from 11.0.0 to before 11.1.1, an unhandled error is thrown when validating invalid connectionParams which crashes a tRPC WebSocket server. This allows any unauthenticated user to crash a tRPC 11 WebSocket server. Any tRPC 11 server with WebSocket enabled with a createContext method set is vulnerable. This issue has been patched in version 11.1.1.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":8.7},"cvss_v3":null,"cwes":["CWE-248"],"references":["https://github.com/trpc/trpc/commit/9beb26c636d44852e0f407f3d7a82ad54df65b4d","https://github.com/trpc/trpc/security/advisories/GHSA-pj3v-9cm8-gvj8"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:01:11.054312287+00:00"},"epss":{"cve":"CVE-2025-43855","score":0.00423,"percentile":0.36625,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-pj3v-9cm8-gvj8","url":"https://osv.dev/vulnerability/GHSA-pj3v-9cm8-gvj8","summary":"tRPC 11 WebSocket DoS Vulnerability","modified":"2025-04-24T16:27:17.713097Z","packages":[{"ecosystem":"npm","name":"@trpc/server","purl":"pkg:npm/%40trpc/server","ranges":[">=11.0.0 <11.1.1"],"fixed":["11.1.1"]}]}],"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."]}