Description
An issue was discovered in lib/Server.js in webpack-dev-server before 3.1.6. 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://127.0.0.1:8080/ connection from any origin.
References (3)
Core 3
Core References
Exploit, Third Party Advisory x_refsource_confirm
https://github.com/webpack/webpack-dev-server/issues/1445
Exploit, Third Party Advisory x_refsource_misc
https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages
Patch, Third Party Advisory x_refsource_confirm
https://github.com/webpack/webpack-dev-server/commit/f18e5adf123221a1015be63e1ca2491ca45b8d10
Scores
CVSS v3
7.5
EPSS
0.0243
EPSS Percentile
82.3%
Attack Vector
NETWORK
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Details
CWE
CWE-20
Status
published
Products (2)
npm/webpack-dev-server
0 - 3.1.11npm
webpack.js/webpack-dev-server
< 3.1.6
Published
Sep 21, 2018
Tracked Since
Feb 18, 2026