# Secure Signing Using External HSM

DevFeed: [Secure Signing Using External HSM](<https://devfeed.tech/articles/secure-signing-using-external-hsm-13953.md>)

Original publisher: [Read original article](<https://developer.espressif.com/blog/secure-signing-using-external-hsm/>)

Author: John Lee

Published: 2023-02-09T00:00:00Z

Content type: tutorial

Language: en

Sources: [Blog on Developer Portal](<https://devfeed.tech/sources/blog-on-developer-portal.md>)

Topics: [ESP32](<https://devfeed.tech/topics/esp32.md>), [Security](<https://devfeed.tech/topics/security.md>), [Cryptography](<https://devfeed.tech/topics/cryptography.md>), [Embedded Software Dev](<https://devfeed.tech/topics/embedded-software-dev.md>)

Tags: [blog](<https://devfeed.tech/tags/blog.md>), [cryptographic](<https://devfeed.tech/tags/cryptographic.md>), [digital](<https://devfeed.tech/tags/digital.md>), [esp32](<https://devfeed.tech/tags/esp32.md>), [esptool](<https://devfeed.tech/tags/esptool.md>), [external](<https://devfeed.tech/tags/external.md>), [firmware](<https://devfeed.tech/tags/firmware.md>), [hardware](<https://devfeed.tech/tags/hardware.md>), [iot](<https://devfeed.tech/tags/iot.md>), [release](<https://devfeed.tech/tags/release.md>), [secure-boot](<https://devfeed.tech/tags/secure-boot.md>), [security](<https://devfeed.tech/tags/security.md>), [signing](<https://devfeed.tech/tags/signing.md>), [ubuntu](<https://devfeed.tech/tags/ubuntu.md>)

## AI overview

This tutorial explains how to use an external Hardware Security Module with Espsecure.py to sign ESP32 firmware through the PKCS #11 interface. It demonstrates a YubiKey 5 Series setup and describes supported Secure Boot V2 signing algorithms.

## Source excerpt

Overview# ESP32 series of chips supports secure boot scheme to allow only trusted firmware to execute from its flash storage. However, this requires careful management of the secure signing key, it must be generated and stored in a secure manner by the signing entity. External HSM (Hardware Security Module) is specially designed cryptographic device that safeguards and manages secrets. HSM also provides specialised cryptographic services like encryption, digital signing etc.