RE-ENCRYPTION FOLLOWING AN OTP UPDATE EVENT

An apparatus and method are described, the apparatus comprising memory control circuitry configured to control access to data stored in memory, and memory security circuitry configured to generate encrypted data to be stored in the memory, the encrypted data being based on target data and a first one-time-pad (OTP). In response to an OTP update event indicating that the first OTP is to be updated to a second OTP different to the first OTP, the memory security circuitry is configured to generate a re-encryption value based on the first OTP and the second OTP, and the memory security circuitry is configured to issue a re-encryption request to cause updated encrypted data to be generated in a downstream component based on the encrypted data and the re-encryption value and to cause the encrypted data to be replaced in the memory by the updated encrypted data.