Select the Office version from the above link and try downloading any updates / add-ins related to that
specific version. It will lead to a validation link (Refer the screenshot below) which will check whether the office
installed in the system is genuine or not. In short the OGA validation generates a hash out of information
gathered from the installed MS Office and passes it on to the server for verification. The user will be
directed to the download link only if the installed office version is genuine.
To defeat such validation, follow the extremely simple steps –
- Select the add-ins / updates that you require for office
- In the Validation required page, copy the file name
Other Ways to Bypass the Windows genuine advantage Validation - The Ethical Hacking
Use google and search for the filename using the following search keyword combination:
site:download.microsoft.com/download
For Example: To search for the file name “RedactionSetup.msi” use the following search key
combination site:download.microsoft.com/download RedactionSetup.msi
- The above search result spits the direct link to the file available on the Microsoft download server
which can be used to directly download the file without any validation check (Refer the screenshot
below for details).
Other Ways to Bypass the Windows genuine advantage Validation - The Ethical Hacking
It is possible to re-use the hash generated in any machine having genuine copy of MS Office and can be
distributed over the internet.
For example – The table below has hashes for downloading rhdtool.exe and RedactionSetup.msi which can be
re-used by any user having pirated copy of Office to defeat OGA validation check.
http://www.microsoft.com/downloads/details.aspx?FamilyID=144E54ED-D43E-42CA-BC7B-
5446D34E5360&displaylang=en&Hash=[Put the hash here]
Other Ways to Bypass the Windows genuine advantage Validation - The Ethical Hacking
Method 3: A Quick Analysis of OGACheckControl.dll
Last but not the least is analyzing OGACheckControl.dll and preparing a patch. However just to keep
myself away from those scary legal notices, I do not want to release any patch at this point of time. I did a
quick reverse analysis while I was about to finish my last latte; below are few interesting sections which one
may like to look at without wasting much of time -
a. Creation of Hash -> Hashing the stream of data and computation of cryptographic hash of a stream of data
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