CERT-TO-EFI-SIG-LIST(1) User Commands CERT-TO-EFI-SIG-LIST(1)

# [NAME](#NAME)

cert-to-efi-sig-list - tool for converting openssl certificates to EFI signature lists

# [SYNOPSIS](#SYNOPSIS)

**cert-to-efi-sig-list** \[*-g &lt;guid&gt;*] *&lt;crt file&gt; &lt;efi sig list file&gt;*

# [DESCRIPTION](#DESCRIPTION)

Take an input X509 certificate (in PEM format) and convert it to an EFI signature list file containing only that single certificate

# [OPTIONS](#OPTIONS)

[**-g** &lt;guid&gt;](#g)

Use &lt;guid&gt; as the owner of the signature. If this is not supplied, an all zero guid will be used

# [EXAMPLES](#EXAMPLES)

To take a standard X509 certificate in PEM format and produce an output EFI signature list file, simply do

cert-to-efi-sig-list PK.crt PK.esl

Note that the format of EFI signature list files is such that they can simply be concatenated to produce a file with multiple signatures:

cat PK1.esl PK2.esl &gt; PK.esl

If your platform has a setup mode key manipulation ability, the keys will often only be displayed by GUID, so using the -g option to give your keys recognisable GUIDs will be useful if you plan to manage lots of keys.

# [SEE ALSO](#SEE_ALSO)

[sign-efi-sig-list(1)](/man/enterprise-packages/efitools/sign-efi-sig-list.1) for details on how to create an authenticated update to EFI secure variables when the EFI system is in user mode.

October 2026 cert-to-efi-sig-list 1.9.2

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Document: cert-to-efi-sig-list(1) from efitools 1.9.2.3.6-r8 (Chainguard OS)
Source: https://git.launchpad.net/ubuntu/+source/efitools
