> 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/xss/reflected-xss-with-custom-tags-only.md).
# 仅使用自定义标签的反射型 XSS
仅使用自定义标签的反射型 XSS 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。
### 反射型 XSS 注入 HTML 上下文，所有标签都被阻止，只有自定义标签除外
此应用会阻止所有“经典”HTML 标签；只允许自定义元素。实验的目标是注入一个可自动执行的自定义标签 `alert(document.cookie)` （这里你希望通过 alert 窃取会话 cookie）。
观察与方法（改写）
* 由于所有标准标签都被过滤，技巧是定义/插入一个浏览器会接受的自定义标签。
* 自定义标签可以包含事件处理器——但某些事件只有在元素能够获得焦点时才会触发。
* 自定义元素默认无法聚焦；因此有必要通过添加以下内容强制其获得焦点 `tabindex=1` 这样在交互时（例如点击或按 Tab 切换）相关事件就会运行。
1. 简单标签——不可聚焦（不会执行 alert）：
```javascript
HELLO
```
2. 同样的标签，通过添加以下内容使其可聚焦 `tabindex` — `onfocus` 可正常工作：
```javascript
HELLO
```
最终概念验证（通过重定向外带数据）
* 我们构造一个 URL，通过一个 `onfocus` 调用 `alert(document.cookie)` 并通过以下方式强制获得焦点 `tabindex=1`.
* 发送给受害者的示例载荷（注入内容已在以下 search 参数中进行 URL 编码 `search` 参数）：
{% code overflow="wrap" %}
```javascript
```
{% endcode %}
---
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