Compromise Boot Memory - EX-0004
Definition
The attacker manipulates memory and configuration used in the earliest stages of boot so that their code runs before normal protections and integrity checks take hold. Targets include boot ROM vectors, first-stage/second-stage bootloaders, boot configuration words and strap pins, one-time-programmable (OTP) fuses, non-volatile images in flash/EEPROM, and scratch regions copied into RAM during cold start. Techniques range from replacing or patching boot images to flipping configuration bits that alter trust decisions (e.g., image selection, fallback order, watchdog behavior). Faults can be induced deliberately (timed power/clock/EM glitches) or via crafted update/write sequences that leave a partially programmed but executable state. Once resident, the modification can insert early hooks, disable or short-circuit checks, or select downgraded images; destructive variants corrupt the boot path to induce a persistent reset loop or safeing entry (a denial of service). Because boot logic initializes buses, memory maps, and handler tables, even small changes at this stage cascade, shaping how command handlers load, how keys and counters are initialized, and which peripherals are trusted for subsequent execution.
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