Microsoft has discovered a vulnerability in Office Visual Basic for Applications (VBA) macro project signing. This vulnerability might enable a malicious user to tamper with a signed VBA project without invalidating its digital signature.

When people run your VBA macro, Office will check the signature and the certificate it was signed with. Adding a time stamp to your signature means that your macro will still be treated as signed, even after your certificate has expired, as long as the certificate isn't revoked.

A digital signature is an electronic, encrypted, stamp of authentication on digital information such as email messages, macros, or electronic documents. A signature confirms that the information originated from the signer and has not been altered.

A digital signature is an electronic, encrypted, stamp of authentication on digital information such as email messages, macros, or electronic documents. A signature confirms that the information originated from the signer and has not been altered.

This article explains how you can get or create a digital signature for use in Office documents. To learn more about how to use them in Office documents, see Add or remove a digital signature in Office files.

When you sign a signature line, you add a visible representation of your signature and a digital signature. In the file, right-click the signature line and choose Sign.

Insertions and deletions of signature lines are treated as changes in the document. Therefore, before the first participant adds their signature, all additions and deletions of signature lines must already be complete. Here’s a rapid graphic summary of all of that.

To resolve this issue, update to the latest version of Mac and iOS apps. Verify the configuration of AD FS 2012 R2 to let users sign in by using an alternative user identifier.

Certificates are moved to the device via email. You will need to export a password-protected .pfx file, and email it to yourself. Then tap on that .pfx file to install it onto the device/Outlook mobile. The following image shows how manual certificate delivery works in iOS.

A digital signature is used to authenticate digital information — such as form templates, forms, e-mail messages, and documents — by using computer cryptography. Once a form is signed, either the entire form or part of the form that was signed cannot be altered without invalidating the signature.