Instruction Set Architecture and Hardware Vulnerabilities

• Instruction Set Architecture (ISA)
• ISA is the part of the processor that defines the instructions that a CPU can execute. It serves as the interface between software and hardware.
• Instructions: The commands the CPU can execute (e.g., arithmetic operations, data movement, control flow).
• Registers: Small, fast storage locations within the CPU that are used to hold instructions and data.
• Data Types: Specifies the types of data the CPU can process (e.g., integers, floating-point numbers).
• Addressing Modes: Techniques for specifying the location of operands for instructions (e.g., immediate, direct, indirect addressing).
• Types of ISA

  CISC

  RISC
• Hardware vulnerabilities are weaknesses in computer hardware that can be exploited to compromise system security.
• Timing Attacks: Exploiting variations in time taken to execute cryptographic algorithms.
• Power Analysis Attacks: Monitoring power consumption to extract cryptographic keys.
• Meltdown:

  • Exploits out-of-order execution to read arbitrary memory, bypassing security boundaries enforced by the CPU.
  • Affects mostly Intel CPUs.
• Spectre:

  • Exploits branch prediction and speculative execution to access restricted data.
  • Affects many types of processors, including those from Intel, AMD, and ARM.
• Mitigation: Various strategies, including software patches, hardware upgrades, and best practices in coding and hardware design, can reduce the risk of exploitation.