> For the complete documentation index, see [llms.txt](https://books.spartan-cybersec.com/web/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://books.spartan-cybersec.com/web/websockets/lab-1-manipulating-websocket-messages-to-exploit-vulnerabilities.md).

# Lab #1: Manipulating WebSocket messages to exploit vulnerabilities

Inicialmente dejamos apagado la intercepción:

<figure><img src="/files/ChOAZt16GTateNnPszgY" alt=""><figcaption></figcaption></figure>

Luego nos dirigimos a `live chat`&#x20;

<figure><img src="/files/IEzKYrrpPrk8KU49qSFZ" alt=""><figcaption></figcaption></figure>

Y luego de acceder a live chat, se genera trafico utilizando websockets:

<figure><img src="/files/5z6ZvB8DtXDMRZRXOE2O" alt=""><figcaption></figcaption></figure>

Luego simplemente localizamos una peticion to server y la enviamos al repeater para posteriormente enviar una carga maliciosa de XSS:

<figure><img src="/files/fN2Gj7PXQx7g22Teu2s8" alt=""><figcaption></figcaption></figure>

Luego de enviar la carga previa podemos apreciar el despliegue de la alerta:<br>

<figure><img src="/files/mK6SVNyv9oLD6RG9t0ju" alt=""><figcaption></figcaption></figure>

Lo anterior, es debido a que los mensajes se cargan en el DOM del HTML:

<figure><img src="/files/nyzE1zcrjuADw4q6gTzS" alt=""><figcaption></figcaption></figure>


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