{"cve":"CVE-2026-27193","nvd":{"published":"2026-02-21T05:17:28.827","modified":"2026-06-17T10:26:49.503","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, all HTTP request headers are stored in the session cookie, which is signed but not encrypted, exposing internal proxy/gateway headers to clients. The OAuth service stores the complete headers object in the session, then the session is persisted using cookie-session, which base64-encodes the data. While the cookie is signed to prevent tampering, the contents are readable by anyone by simply decoding the base64 value. Under specific deployment configurations (e.g., behind reverse proxies or API gateways), this can lead to exposure of sensitive internal infrastructure details such as API keys, service tokens, and internal IP addresses. This issue has been fixed in version 5.0.40.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","score":8.2},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N","score":5.3},"cwes":["CWE-200"],"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-9m9c-vpv5-9g85"],"products":["feathersjs:feathers"],"source":"nvd","synced_at":"2026-10-19T22:24:17.937441719+00:00"},"epss":{"cve":"CVE-2026-27193","score":0.00398,"percentile":0.3406,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-9m9c-vpv5-9g85","url":"https://osv.dev/vulnerability/GHSA-9m9c-vpv5-9g85","summary":"Feathers exposes internal headers via unencrypted session cookie","modified":"2026-02-23T23:43:57.119633Z","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."]}