Hardware Security
Which correctly pairs why cold boot attacks work with a typical countermeasure?
- ADRAM erases instantly at power-off; keep the power on
- BHeating DRAM makes contents easier to read; add cooling
- CDRAM contents persist for seconds to minutes after power-off, longer when cooled; encrypt memory contents
Show answer and explanation
Answer: C. DRAM contents persist for seconds to minutes after power-off, longer when cooled; encrypt memory contents
DRAM cell charge does not disappear immediately when refresh stops; contents largely persist for seconds to minutes, and longer at low temperature. Removing the memory from a just-powered-off PC and reading it elsewhere can reveal secrets such as disk encryption keys. Countermeasures include hardware memory encryption, erasing keys at shutdown and keeping keys only inside the CPU.
- A. The charge does not vanish instantly.
- B. Cooling makes contents persist longer.
- C. Correct. Encrypted contents are useless if read.