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View Full Version : ICQ & MSIE Allow Arbitrary Code Execution


Paul Wilders
July 17th, 2002, 04:06 AM
"It does infact allow you to run code of your choosing on a victims machine by creating a specially crafted webpage and sound scheme file

Explaination and example

The finder has created an example exploit on:

www.xs4all.nl/~jkuperus/icq/icq.htm (http://www.xs4all.nl/~jkuperus/icq/icq.htm)

that starts a little flame program

It works as followed

the default action for icq soundscheme (scm) files is open it places the wav files included with the scm file in a known location on the hard disk.

flame.scm wil be downloaded and installed in C:Program FilesICQSoundsflame[1]
the scm file i use creates a auth.wav file .

In reality however this is not a wav file but a mht (mail archive file) with en embeded base64 encoded executable

then he uses one of the many available local code execution vulnerabilities found in internet explorer recently to execute the embedded binary with this url :

deleted - Forum Admin

The author doesn't think its necessary to use one of ie's exploit as you can also call html files in the mht archive, But for some reason wasn't able to get this to work right away.

Workaround

For a short term solution

open explorer (the file manager not the browser)
go to the file types tab in tools > folder options

locate the scm extention and change the default behaviour to prompt before download

In the long term icq will have to use something like random foldernames for soundschemes to prefent this from happening."

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note: using the mentioned URL is your own responsebility - Forum Admin

regards.

paul