Why MS Excel Markos digitally sign can be?


It is possible to program macros digital sign by a CA authority, e.g.. thawte. Thus the following dialog when you open the Excel workbook under certain circumstances can prevent:

sicherheitswarnung_markos

This security query has the purpose to protect the PC against attacks with malicious Excel and Word documents, like in the annex of distributed spam mails.

Benefits of certified macros:

  • About the MS Trust Center, you can define the behavior for Markos for all Office applications. It's possible, that there the settings “Disable all macros except digitally signed macros” is set, then the macro must not be enabled by the user. The same applies to the setting “Enable all macros”.
  • The problem is, that by default this option on “Disable all Markos with Benachichtigung” is used and thus the user with certificate must always act, unless, the system administrator has set right this when setting up the PCs for users.
makroeinstellungen

Options for macro security in Excel Syncho settings

 

Disadvantages:

  • Certification cost from €269 – 679€ (for the duration of a certificate of 1 – 3 Years)
  • If the macro I change code (not the workbook) must the certificate be renewed, what works automatically, If you have a valid certificate installed on the PC