How to ‘hack’ an excel spreadsheet

Something many people don’t seem to realize is once a person has physical access to a database the only thing seperating them from getting into it is a little knowledge.  This is why web apps are much more easily secured than downloadable apps could ever be.

Such is the situation with excel spreadsheets.  They use such laughably easy to break encryption that even the slowest computers can be into them in seconds.  If you’ve ever forgotten your password to an excel spreadsheet check out the macro posted on McGimpsey’s website.

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  1. #1 by Richard Ferlatte on January 22, 2011 - 9:46 am

    I couldn’t agree more.

    You’d think that Microsoft would invest more time and energy in building up Excel’s encrytion. There’s a lot of “in-house” excel applications out there and the only thing protecting the spreadsheet from prying eyes is this poor excuse for security.

    When I have to use excel that requires encrytion – I using wrap the excel application with a VB dll that compiles the code and sensitive information (such as database connection strings and queries)

    Great link….I have a few spreadsheets to hack into 😉

    • #2 by Anthony on January 25, 2011 - 6:05 pm

      I’m glad you like it! I hope you don’t have any troubles retrieving your lost passwords 😉

      Though, FYI, compiling connection strings, passwords, etc, into a dll isn’t much safer. Have you ever viewed your dll in a hex editor? Or tried searching in your dll file for the word “connection” or “password” using a tool like AgentRansack? You’ll quickly find that your password isn’t as secure as you may think it is.

      • #3 by Richard Ferlatte on January 26, 2011 - 6:05 pm

        Ah so very true….

        In the end….everything is “hackable” if the user is determined to get in. It’s just depends on how easy you want to make it for them.

  2. #4 by Bob Daley on April 13, 2013 - 5:20 pm

    What I have is a 2003 spread sheet that works pretty well. What I want to do is get the code so that I can convert it into a web based project. How hard will this be?

    • #5 by Anthony on April 16, 2013 - 1:07 pm

      Oh my, well, my two second analysis says, it will be hard.

      Spread sheet technology is not the same as web technology. VBScript (what excel uses) does not at all look like .Net code (the current Microsoft platform). Once upon a time, around 8 years ago, Visual Basic looked more like VBScript ant it was used to power websites. Visual Basic has been obsolete for some time now (Microsoft has abandoned it for years now).

      A spread sheet provides you with two main things, 1) a integrated database 2) a integrated user interface. Both these things are neatly packed up and you don’t even notice the separation. On the web this difference is much greater. You would have to port your data to a real database (say SQL server) and hopefully also normalize it. Then you would also need to re-map all of your methods to work with a web UI. Generally speaking you will be re-writing your entire user interface.

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