Georgi Guninski raises an interesting question:
Digitally signing buggy ActiveX components
Date: 14 February 2002
This is just an unverified suspicion. I don't claim this information is
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Back in 1999 Juan Carlos Garcia Cuartango <cuartangojc@MX3.REDESTB.ES> made
excellent point at:
3- Even if Microsoft fixes the hole the hole could exist forever. Why ?
As far as I know this is the first time a hole is "SIGNED".
MS has released an "dhtmed.cab" file as an ActiveX component signed by
Here is more on this.
ActiveX in internet explorer allows downloading from the web and installing
signed components (native code) on the user computer.
As history shows a lot of ActiveX components are buggy and new version is
released. The interesting part is the buggy version is still really signed
available in one form or another.
A pure hypothethical scenario is to try to install the old buggy signed
if the user don't have it or on top of the patched one.
Basically this is done this way:
So, I wonder whether doing such mischief may lead to old exploits start
Don't know whether this is a real threat, this is just a suspicion.
Anyway, to prevent such stuff, in internet explorer security options
disable everything that contains "active".
Or at least if you see a prompt "...This is digitally signed by X..."
think do you really trust X having in mind his security record.