playing for fun with <=IE7

Impact: who knows ...

Fix Available: no

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1) Bug

2) Proof of concept

3)Conclusion

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1) Bug

======

it's possible to bypass the extension filter of <=IE7  this can result by downloading

an arbitrary exe file

=====

2)proof of concept

=====

let's take this exemple :

http://dams083.free.fr/tmp/putty.exe

this is simply putty .

you click on this and then you will be prompted for downloading the file.

but what about if we do :

http://dams083.free.fr/tmp/putty.exe?1.txt

... the .exe is showed.

now let's go a bit ahead :

http://dams083.free.fr/tmp/putty.exe?1.cda

wow my .exe is downloaded directly and located in temporary files ( and """opened""" by windows media player).

works with theses extension :

.log

.dif

.sol

.htt

.itpc

.itms

.dvr-ms

.dib

.asf

.tif

etc ...

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5) Conclusion

=====

this is very funny , because actually it only works for .exe extensions.

.COM , .PIF , etc  you CANT do this. ( overwrite the extension , and then bypass the filter)

i guess we can wonder what the heck.

regards laurent gaffi