A high-severity vulnerability has been fixed in WinRAR, the popular file archiver utility for Windows used by millions, that can execute commands on a computer simply by opening an archive.

  • C8H10N4O2
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    11 year ago

    How does an unchecked buffer overrun result in dropping to a shell inside the containing process though?

    • Nougat
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      11 year ago

      I’m not super clear on that, and I’m eager to have someone inform/correct me, but here’s my understanding:

      It’s like a crash. The running program tells the system to address memory that is not available to be addressed, and the system goes “Uh, what?” and drops into a state where it has stopped following the code from the initial thread (which I am sure is not the right terminology) and waits blankly for new code to be received.

      Then the still running-but-“hung” process delivers that “arbitrary code,” and the system dutifully executes it.