Windows AIM Client Exploits

From: Robbie Saunders (ihostat_private)
Date: Sun Dec 30 2001 - 15:56:47 PST

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     ('binary' encoding is not supported, stored as-is)
    i have generated a list of exploits that can be used to 
    cause an illegal operation on windows aim clients
    
    1. Comment Crash - anyone remember that neat little 
    exploit that involved a large amount of html comment 
    headers "<!-- "? to fix it they configured the server to 
    ignore instant messages over 2550 characters 
    instead of the previous 7950, making it seemingly 
    impossible to send the long string, but it turns out you 
    can send the full string in a chat invite message.
    
    2. Long Name Crashes - any kind of "extra" features 
    involving names (file names, game names, buddy list 
    names, etc.) can be used to crash the remote aim 
    client by sending an unusually long name (like 6000 
    #'s for example)
    
    3. Font Buffer Crash - by sending lots of different 
    fonts in an im or two you can fill up aim's recent font 
    name buffer which disables all "new" html codes (any 
    html header that the client hasn't already used in the 
    open im window). for example, links turn up as 
    normal text and new fonts are converted to the 
    default font. it seems aol miscoded something and 
    sending a horizontal line "<hr>" causes the client 
    crash after you fill up the font buffer
    
    4. Large Buddy Icon Crash - you can freeze 
    someone's computer for a short (or long) amount of 
    time by sending someone a small .gif file edited to be 
    very large (like 10,000x10,000) as a buddy icon
    
    5. Future Problems? - sending an invalid chat url in a 
    chat invite (like using two !'s instead of one) causes a 
    blank modal to pop up, sending the character &#8211; (150) 
    gives the remote aim a neat little font error, and you 
    can send image headers (and maybe images) in 
    game invites
    
    i have updated my aim filter software to use and 
    block the above exploits, and it can be downloaded at 
    http://www.ssnbc.com/wiz/
    
    <all exploits were discovered by or largely contributed 
    to by robbie saunders>
    



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