Re: WordPad/riched20.dll buffer overflow

From: Ussr Labs (labsat_private)
Date: Tue Nov 23 1999 - 17:06:45 PST

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    Well, I find SOME ways to CRASH (no exploit possibly), in another place in
    the format rft, in the richie20.dll, making a EATER OF STACK,
    Inside in the rtf file,
    
    One rtf inside of another with OLE, the ole(wordpad), crash , with a STACK
    OVERFLOW EXCEPTION FILTER,
    
    EXAMPLE RTF CODE:
    
    {\rtf1\ansi\ansicpg1252\deff0\deftab720{\fonttbl{\f0\fswiss MS Sans
    Serif;}{\f1
    \froman\fcharset2 Symbol;}{\f2\froman Times New Roman;}{\f3\froman Times New
    Ro
    man;}}
    {\colortbl\red0\green0\blue0;}
    \deflang1033\horzdoc{\*\fchars }{\*\lchars }\pard\plain\f2\fs20
    hello!!!!{\obje
    ct\objemb{\*\objclass WordPad.Document.1}{\*\objname
    Object1}\objw11115\objh293
    {\*\objdata
    BUFFER)
    }}}\plain\f2\fs20 !!!!!!!!!!!!!!!!
    \par }
    
    WERE BUFFER IS LIKE 9K OF (123456789ABCDEFGHIJKLMNOPQRSTUVWYZ)
    
    
    
    But its just eat the stack, OLE crash, and not are possibly make exploit on
    this.
    
    is another example of another bug in ole/riche20.dll all in wordpad.exe
    
    
    Ussrlabs
    
    I have another example same happen in word files, personally I did a .doc
    file, if you run it machine reset in Microsoft word 2000, 97, in windows 98,
    and in nt crash and leave word in memory (present) like a memory process
    leek, but its just a bug no way to exploit it, the only thing possibly is
    reset the machine in windows 98 :).
    
    
    
    u n d e r g r o u n d  s e c u r i t y  s y s t e m s  r e s e a r c h
    http://www.ussrback.com
    
    
    >My assertion was based on a cursory look and the fact the return address
    >_is_ overwritten. I'll bow to the greater and more indepth analysis of
    >USSRLABS and Solar Eclipse. No doubt, however, there will be buffer
    overruns
    >elsewhere within the application and not just after the {rtf1\AA...} part.
    >I've not actually looked but if you do I can almost guarantee there will be
    >more. Perhaps one of these will _not_ be restricted to A-Z and a-z and then
    >it would have a chance of being exploitable. For example there is an
    >{operator Name-Goes-Here} part of a windows RTF file. By doing
    >{operatorAAA.... Name} or {operator AAAA...} may cause a buffer overrun -
    >and one where the return address is overwritten and any characters are
    >allowed. This is mostly conjecture however. Anyone with the time or
    >inclination could check on this or any of the other rtf headers.
    



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