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How to Sign Files with Microsoft SignTool?

The signtool.exe is used to sign or timestamp codes, certificates, etc. Depending on the OS version the tool may be located in different folders (e.g. Windows 10/x64: C:\Program Files (x86)\Windows Kits\10\bin\x64\signtool.exe).

For more information on the tool location, please refer to the Microsoft documentation.

Example – with certificate reference by subject name:

signtool.exe sign /v /fd sha256 /sm /n "signtooldemo.hsmdemo.test" Application-ToSign.exe

The following certificate was selected:
    Issued to: signtooldemo.hsmdemo.test
    Issued by: signtooldemo.hsmdemo.test
    Expires:   Thu Feb 14 16:31:30 2019
    SHA1 hash: CB1A55F6AB8CCACEDAB3FCD9DE48BD69BE16B88D

Done Adding Additional Store
Successfully signed: ApplicationToSign.exe

Number of files successfully Signed: 1
Number of warnings: 0
Number of errors: 0

Example – with certificate reference by SHA1 hash:

signtool.exe sign /v /fd sha256 /sm /sha1 "cb1a55f6ab8ccacedab3fcd9de48bd69be16b88d" ApplicationToSign.exe
warning

Take care, that the certificate references are unique, otherwise, the signing process could fail (subject name, or sha1 value of the certificate). Referencing the certificate by CSP (/csp) and key container (/kc) seems to fail (reason yet not known).

For signing and verification options, please refer to signtool.exe help and the Microsoft documentation.

Verifying Signed File​

The signature can be verified either on the command line or using the file properties dialog (Digital Signatures). The signature can be verified either via Graphical User Interface (GUI) or via Command line interface (CLI).

Here is an example for each case:

Below is an example of how to verify using the file properties:

  • Navigate to the properties of the signed file you would like to verify,
  • Open the Digital Signatures tab,
  • Double click the signature in the Signature list,
  • On the General tab click on View Certificate,
  • The certificate information is shown.