{"id":"CVE-2018-14731","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-14731","generatedAt":"2026-10-29T00:47:41.091Z","title":"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).","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.","published":"2018-09-21T17:29:05.000Z","lastModified":"2026-06-17T01:41:32.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":7.5,"severity":"HIGH","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},"cwe":["CWE-200"],"affected":["parceljs/parcel"],"epss":{"score":0.02327,"percentile":0.83423,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (2.33%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/parcel-bundler/parcel/issues/1783","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/parcel-bundler/parcel/pull/1794","tags":["Exploit","Patch","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/parcel-bundler/parcel/issues/1783","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/parcel-bundler/parcel/pull/1794","tags":["Exploit","Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-14731","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}