GoKawiilNordic Semiconductor engineer details debugger pitfall in nRF54L Key Management Unit
A Nordic Semiconductor engineer, newly joined to the company, describes debugging the security architecture of the nRF54L chip series by directly manipulating registers rather than writing firmware. While probing the Key Management Unit (KMU), which stores sensitive key data in a Secure Information Configuration Region only accessible in secure mode, they encountered unexpected memory values traced to how the debugger interacts with the chip's internal components rather than a flaw in the KMU itself.