i8igmac Posted April 16, 2015 Share Posted April 16, 2015 Any one experience a locked xlsx document, I'm looking for ways to crack this password protected file... my employer employed a IT guy to help design a new invoice for our company, the relationship just ended and bad terms with this techy, he does not respond to our emails... I was asked if this password could be cracked. This was a request made only a few minutes ago, and my Google searchs lead to winblows malware... I won't have access to my laptop until tonight. so I appreciate any advice you guys can give. John the Ripper is in my mind Quote Link to comment Share on other sites More sharing options...
cooper Posted April 16, 2015 Share Posted April 16, 2015 This thread on the HashCat forum describes how to do it with a HashCat / JtR combo type thing. Quote Link to comment Share on other sites More sharing options...
digip Posted April 16, 2015 Share Posted April 16, 2015 (edited) just about anything can be cracked if its easily guessed dictionary and relative language that doesn't use special character types but I don't know of any tools that hook the authentication process for excel files.I know you can tie word lists to open password protected zip files in Linux but you'd probably have to write your own similar tool for excel since there are so many different versions of office I'm not sure how that works. I'd steer clear of apps claiming to do it of you can't view the source code though. check git to see if anyone has a Linux script or even powershell hooks to open office docs and then tie in a word list somehow. windows may have a comand line sequence to open password protected office docs and if so all you would need then is a way to script a word list against it Edited April 16, 2015 by digip Quote Link to comment Share on other sites More sharing options...
sud0nick Posted April 16, 2015 Share Posted April 16, 2015 I found this forum through a quick Google search. I have never tried any of these methods but some of them sound like they're worth a shot. (http://community.spiceworks.com/topic/328118-need-to-unlock-a-password-protected-excel-2010-workbook) Some of the noteworthy attempts are: 1. Move it to Linux and open with Open Office. Some people claim it will open without regard to the password. However, since the file is supposed to be encrypted with that password I'm not sure this will work. 2. If you can open the file but not edit you may be able to use VBA code to brute force the password. 3. Upload to Google Docs and download as a regular workbook (if you can access it and not edit) Many of the users on that forum are claiming the VBA code in one of the posts works perfectly for bypassing the password in 2013 but I would execute it in a VM just to be careful. VBA code can be dangerous if you don't know exactly what it does. Quote Link to comment Share on other sites More sharing options...
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