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 Forums >>  Brainstorms - General  >>  Possible Anti-Debugging Technique Question

Topic created on: January 14, 2011 00:02 CST by admax88 .

I'm trying to reverse engineer an old windows program.  It was released around 1998.

I have the program open in OllyDbg, and there is a certain area of memory that even while the program is paused, the contents change every time I attempt to read it.

Has anyone encoutered something like this?  Olly reports that the memory acces is "RW Guarded".

Thanks for the help.

  NirIzr     June 24, 2011 18:29.40 CDT
perhaps accessing still causes the gourd exception to raise and it does something with the data? doesn't sound likely but given the info you provided that was my first idea.
also, is this a windows XP app or is it supposed to run under lesser versions of windows? cause if its not XP, there might be some variations that will cause such a thing.
i assume it doesn't run of some embedded device so hardware malfunctions are out of the way.. have you tried other debuggers of reading the memory yourself using winapi?
i couldn't thing of other ways code might be executing.. are you sure you suspend the whole process and not just some of its threads?

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