{"cve":"CVE-2018-14731","nvd":{"published":"2018-09-21T17:29:05.140","modified":"2026-06-17T01:41:32.050","status":"Modified","description":"An issue was discovered in HMRServer.js in Parcel parcel-bundler. Attackers are able to steal developer's code because the origin of requests is not checked by the WebSocket server, which is used for HMR (Hot Module Replacement). Anyone can receive the HMR message sent by the WebSocket server via a ws://127.0.0.1 connection (with a random TCP port number) from any origin. The random port number can be found by connecting to http://127.0.0.1 and reading the \"new WebSocket\" line in the source code.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5},"cwes":["CWE-200"],"references":["https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages","https://github.com/parcel-bundler/parcel/issues/1783","https://github.com/parcel-bundler/parcel/pull/1794","https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages","https://github.com/parcel-bundler/parcel/issues/1783"],"products":["parceljs:parcel"],"source":"nvd","synced_at":"2026-10-19T20:53:14.491561039+00:00"},"epss":{"cve":"CVE-2018-14731","score":0.02327,"percentile":0.83515,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-37q6-576q-vgr7","url":"https://osv.dev/vulnerability/GHSA-37q6-576q-vgr7","summary":"Missing Origin Validation in parcel-bundler","modified":"2023-11-08T03:59:56.925908Z","packages":[{"ecosystem":"npm","name":"parcel-bundler","purl":"pkg:npm/parcel-bundler","ranges":["<1.10.0"],"fixed":["1.10.0"]}]}],"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."]}