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What does kernel code signing EKU do? How can i still load a driver without kernel code signing EKU?

henrik_meidahenrik_meida Member Posts: 83

I recently got my hands on a new certificate, and it came to my notice that it did not have kernel mode code signing EKU in the certificate, but it did have code signing EKU.

I thought for sure that if i use this to sign a driver, it should not load. But it actually did!

So my question is, what does kernel mode code signing EKU in the certificate actually do? How can i load a driver that is signed with a cert without kernel mode code signing EKU?


  • Peter_Viscarola_(OSR)Peter_Viscarola_(OSR) Administrator Posts: 8,704

    I am not aware of a special kernel mode code signing EKU. Can you tell me what that OID is?


    Peter Viscarola

  • henrik_meidahenrik_meida Member Posts: 83

    @Peter_Viscarola_(OSR) said:
    I am not aware of a special kernel mode code signing EKU. Can you tell me what that OID is?


    The OID is the following:

    Kernel Mode Code Signing (

    What's the point of this OID then? I just noticed that some of the certificates that are used to sign drivers don't even have this, and some do. I always thought this OID is required for drivers?

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