Re: Getting passwords from the heap?

From: Jason R. Seats (Jason.Seatsat_private)
Date: Wed Jun 27 2001 - 08:25:13 PDT

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    Dennis McHenry wrote:
    > 
    > From: "Felix von Leitner" <leitnerat_private>
    > > This wasn't perchance a Microsoft operating system you were using?
    > It's been a while since I've done C for a win system, but as I recall Malloc
    > returns zeroed-out chunks.
    > 
    > My response to Jason's point, though, is that if a program doesn't handle
    > sensitive information in a prudent manner (preventing it from being swapped
    > to disk, overwriting the memory space where it was stored, etc.), the
    > information could indeed be in memory.  I'd label this as a programming
    > error for the application that left it's sensitive info. sitting around,
    > rather than an OS problem (I don't recall Windows saying it wiped memory
    > after closing applications).
    > 
    > If you're using a win box, you can use debug to examine memory remnants.
    > 
    
    If you are using the debug version of the C-runtime libs for Windows,
    freed memory is set to a characteristic value so that you can recognize
    if you are ever de-referencing a pointer into freed memory (0x45 is
    think).  You can use the debugger to watch Release built applications
    memory in a realistic way though.
    
    -- 
    Jason Seats
    Information Security Software Engineer
    TechGuard Security
    jason.seatsat_private
    www.techguardsecurity.com
    636-519-4848
    



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