{"cve":"CVE-2026-27192","nvd":{"published":"2026-02-21T04:15:58.697","modified":"2026-06-17T10:26:49.387","status":"Analyzed","description":"Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. In versions 5.0.39 and below, origin validation uses startsWith() for comparison, allowing attackers to bypass the check by registering a domain that shares a common prefix with an allowed origin.The getAllowedOrigin() function checks if the Referer header starts with any allowed origin, and this comparison is insufficient as it only validates the prefix. This is exploitable when the origins array is configured and an attacker registers a domain starting with an allowed origin string (e.g., https://target.com.attacker.com bypasses https://target.com). On its own, tokens are still redirected to a configured origin. However, in specific scenarios an attacker can initiate the OAuth flow from an unauthorized origin and exfiltrate tokens, achieving full account takeover. This issue has bee fixed in version 5.0.40.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","score":7.6},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1},"cwes":["CWE-346"],"references":["https://github.com/feathersjs/feathers/commit/ee19a0ae9bc2ebf23b1fe598a1f7361981b65401","https://github.com/feathersjs/feathers/releases/tag/v5.0.40","https://github.com/feathersjs/feathers/security/advisories/GHSA-mp4x-c34x-wv3x"],"products":["feathersjs:feathers"],"source":"nvd","synced_at":"2026-10-19T22:24:17.937441719+00:00"},"epss":{"cve":"CVE-2026-27192","score":0.0027,"percentile":0.19288,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-mp4x-c34x-wv3x","url":"https://osv.dev/vulnerability/GHSA-mp4x-c34x-wv3x","summary":"Feathers has an origin validation bypass via prefix matching","modified":"2026-02-23T23:43:54.833394Z","packages":[{"ecosystem":"npm","name":"@feathersjs/authentication-oauth","purl":"pkg:npm/%40feathersjs/authentication-oauth","ranges":["<5.0.40"],"fixed":["5.0.40"]}]}],"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."]}