> 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/ja/web/access-control/user-id-controlled-by-unpredictable-guid-parameter.md).

# 予測不能なGUIDパラメータで制御されるユーザーID

予測不能なGUIDパラメータで制御されるユーザーIDの PortSwigger Web Security Academy ラボ向けノート。攻撃フロー、ペイロードテスト、Burp Suite による検証、および是正策の文脈を含みます。

#### パラメータで制御されるユーザーID

このラボでは **水平権限昇格** ユーザーアカウントページの問題。/ その特徴は **ユーザーはGUIDで識別されます**、つまり長くランダムな認証情報です。たとえば：

```bash
9e2f3fc0-7035-48ed-ad6d-f643690c7b9d
```

アカウントに接続した後 **wiener:peter**、［マイアカウント］セクションで自分のGUIDを確認できます。

<figure><img src="https://2001299964-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-1a4b31aaae17a8498c760d2d34a450ca27da9158%2Fimage%20(268).png?alt=media" alt=""><figcaption></figcaption></figure>

#### **公開情報からGUIDを取得する**

サイトを閲覧すると、 **公開されている投稿** に他のユーザーのGUIDが見つかります：

* 管理者のGUIDは彼の投稿の一つに表示されています。

<figure><img src="https://2001299964-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-d3986f80c0b30028730db5f85d5c799ecb875646%2Fimage%20(269).png?alt=media" alt=""><figcaption></figcaption></figure>

同様に、GUIDを次から取得できます **carlos**.

<figure><img src="https://2001299964-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-7a67cce120c504b0da7e8cc1a7789bf06cbcbb1b%2Fimage%20(270).png?alt=media" alt=""><figcaption></figcaption></figure>

```bash
?userId=5abc76d3-7763-4be9-83d1-c6181bcdf0b5
```

#### **操作：Carlosのアカウントにアクセス**

アカウントページは制御可能なパラメータ経由でアクセスできます：

```bash
my-account?id=5abc76d3-7763-4be9-83d1-c6181bcdf0b5
```

自分のGUIDを単に次のものに置き換えるだけで **carlos**、彼のアカウントにアクセスできます：

<figure><img src="https://2001299964-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-6215ffb1c858fefb2e9f8b36c932c2079f2fda1c%2Fimage%20(271).png?alt=media" alt=""><figcaption></figcaption></figure>


---

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