> 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/zh/web/xxe/xxe-file-read-via-external-entities.md).
# 通过外部实体进行 XXE 文件读取
通过外部实体进行 XXE 文件读取笔记，适用于 PortSwigger Web Security Academy 实验室，包括利用流程、载荷测试、Burp Suite 验证和修复上下文。
### 利用外部实体通过 XXE 获取文件
通过声明外部实体利用 XXE 漏洞以恢复文件内容（此处 `/etc/passwd`）从 **检查库存** 该功能会解析 XML 并返回意外值。
该功能发送如下 XML：
{% code overflow="wrap" %}
```xml
2
1
```
{% endcode %}
如果 `` 的数值被字符串替换，那么该值会在响应中回显（这对利用很有用）：
```xml
test
```
1. 在 DOCTYPE 声明中声明一个指向系统文件的外部实体。
```xml
]>
```
2. 在 `` 字段中调用此实体，该字段由应用程序返回。
```
&myFile;
```
3. 响应随后应包含目标文件的内容（`/etc/passwd`).
```xml
]>
&myFile;
1
```
---
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