> 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/ru/web-vulnerabilities/deserialization-yaml-attack/des-yaml-base64-url-pentesting-web.md).

# Десериализация YAML через Base64 URL

В **URL**, содержимое, отображаемое в описании, закодировано в **base64**:

<figure><img src="/files/0ccde43faa550bb5f6828fb31834a38e02be4a25" alt=""><figcaption></figcaption></figure>

Если мы декодируем текст из base64, мы видим, что это действительно соответствует тексту:

<figure><img src="/files/2187a36e41772eb6deffcd34ca3a2faa5ba9db66" alt=""><figcaption></figcaption></figure>

Мы проводим тест, чтобы проверить, можем ли мы **изменить это содержимое** с нашей стороны. Необходимо добавить "yaml:":

<figure><img src="/files/4da8c2a4312cc7a4dee9bf8b903ad88c0d088a33" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/b7e6a818ac8400dab84f4841df09ccd88c2e4f97" alt=""><figcaption></figcaption></figure>

Затем мы пытаемся внедрить команды, в данном случае **id** команду, следующим образом:

```bash
yaml: !!python/object/apply:subprocess.check_output ['id']

```

<figure><img src="/files/f3912d3421f59ad757805f736cabda888381d6d1" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/c766ec9bf52e34b5cd5b8a7917c883f614dc289c" alt=""><figcaption></figcaption></figure>


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