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c#rsadigital-signaturedisksigntool

How to sign ISO disk image files?

I'm attempting to sign .iso(disk image file) file types using Microsoft SignTool.exe. But signtool throws an error

Done Adding Additional Store
SignTool Error: This file format cannot be signed because it is not recognized.
SignTool Error: An error occurred while attempting to sign: C:\isofiles\myiso.iso

Command I have used to sign .iso files:

signtool sign /f "C:\certificate\digicert.pfx" /p certpassword /fd SHA256 /t timestampurl 'C:\isofiles\myiso.iso'

I have also tried to sign .iso files using RSA crypto algorithm. But it generated signature bytes. I'm not sure how to embed the signature into .iso file. Can someone please suggest how to sign .iso file types?

Solution

  • Signing an .iso file directly using SignTool isn't possible because it is designed to sign executable files (like .exe or .dll) and some types of script and document files, but not .iso files. ISO files do not have a structure that supports embedded digital signatures like executable files do.