CWE-1300 类漏洞列表 13

As each character of
		    the PIN number is entered, a correct character
		    exhibits one current pulse shape while an
		    incorrect character exhibits a different current
		    pulse shape.

Rather than comparing
		    each character to the correct PIN value as it is
		    entered, the device could accumulate the PIN in a
		    register, and do the comparison all at once at the
		    end. Alternatively, the components for the
		    comparison could be modified so that the current
		    pulse shape is the same regardless of the
		    correctness of the entered
		    character.

The local method of extracting the secret key consists of plugging the key into a USB port and using electromagnetic (EM) sniffing tools and computers.

Several solutions could have been considered by the manufacturer. For example, the manufacturer could shield the circuitry in the key or add randomized delays, indirect calculations with random values involved, or randomly ordered calculations to make extraction much more difficult. The manufacturer could use a combination of these techniques.