{"cve":"CVE-2026-25223","nvd":{"published":"2026-02-03T22:16:31.130","modified":"2026-07-15T02:18:52.920","status":"Modified","description":"Fastify is a fast and low overhead web framework, for Node.js. Prior to version 5.7.2, a validation bypass vulnerability exists in Fastify where request body validation schemas specified by Content-Type can be completely circumvented. By appending a tab character (\\t) followed by arbitrary content to the Content-Type header, attackers can bypass body validation while the server still processes the body as the original content type. This issue has been patched in version 5.7.2.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-436","CWE-179"],"references":["https://fastify.dev/docs/latest/Reference/Validation-and-Serialization","https://github.com/fastify/fastify/blob/759e9787b5669abf953068e42a17bffba7521348/lib/content-type-parser.js#L125","https://github.com/fastify/fastify/blob/759e9787b5669abf953068e42a17bffba7521348/lib/validation.js#L272","https://github.com/fastify/fastify/commit/32d7b6add39ddf082d92579a58bea7018c5ac821","https://github.com/fastify/fastify/security/advisories/GHSA-jx2c-rxcm-jvmq"],"products":["fastify:fastify"],"source":"nvd","synced_at":"2026-10-19T22:22:27.261130201+00:00"},"epss":{"cve":"CVE-2026-25223","score":0.00862,"percentile":0.58576,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-jx2c-rxcm-jvmq","url":"https://osv.dev/vulnerability/GHSA-jx2c-rxcm-jvmq","summary":"Fastify's Content-Type header tab character allows body validation bypass","modified":"2026-02-04T18:07:32.787861Z","packages":[{"ecosystem":"npm","name":"fastify","purl":"pkg:npm/fastify","ranges":["<5.7.2"],"fixed":["5.7.2"]}]}],"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."]}