How it was found

I would like to report Stored XSS in module "min-http-server". It allows to inject malicious scripts in the file name, store them on the server, then execute these scripts in the browser via the XSS vulnerability.

Module

module name: min-http-server version: 1.0.6 npm page: https://www.npmjs.com/package/min-http-server

Module Description

一个零配置、轻量级的 http 静态资源服务器 means A zero-configuration, lightweight http static resource server

Module Stats

[0] downloads in the last day [4] downloads in the last week [35] downloads in the last month

Vulnerability

Vulnerability Description

This XSS vulnerability occurs due to the module represents filename(s) in HTML without any sanitization in listing directory page. In a result, any malicious scripts which are injected and stored on the server, would be executed in the client's browser.

Steps To Reproduce:

• Install the module

npm install -g min-http-server

• In the directory which will be served via min-http-server, create file with following names in directories ~/Desktop/:

" onmouseover=alert(1) "

{F486143}

• Run 'min-http-server in "~/Desktop" directory :

min-http-server

    [tiny-http-server] static-server is starting at port 1138
    [tiny-http-server] please enter localhost:1138 in the browser

• Open http://localhost:1138/ {F486143}

• When mouseover event is trigger, a message will be popup via XSS vulnerability. {F486145}

Patch

User input should be properly sanitized and filtered both at the client and server side. Dangerous characters such as < > ' " % ; ) ( & + should either be disallowed or HTML encoded before displaying them on screen.

Supporting Material/References:

• Linux kali 4.15.0-kali2-amd64
• node 10.15.3
• npm 6.9
• Firefox ESR 60.5.1esr (64-bit)

Wrap up

• I contacted the maintainer to let them know: N
• I opened an issue in the related repository: N

Impact

It allows to inject malicious scripts in the file name, store them on the server, then execute these scripts in the browser via the XSS vulnerability.