The product performs a power or debug state transition, but it does not clear sensitive information that should no longer be accessible due to changes to information access restrictions.
A device or system frequently employs many power and sleep states during its normal operation (e.g., normal power, additional power, low power, hibernate, deep sleep, etc.). A device also may be operating within a debug condition. State transitions can happen from one power or debug state to another. If there is information available in the previous state which should not be available in the next state and is not properly removed before the transition into the next state, sensitive information may leak from the system.
Threat Mapped score: 3.0
Industry: Finiancial
Threat priority: P2 - Serious (High)
CVE: CVE-2020-12926
Product software does not set a flag as per TPM specifications, thereby preventing a failed authorization attempt from being recorded after a loss of power.
| Phase | Note |
|---|---|
| Architecture and Design | N/A |
Intro: This example shows how an attacker can take advantage of an incorrect state transition.
Body: Suppose a device is transitioning from state A to state B. During state A, it can read certain private keys from the hidden fuses that are only accessible in state A but not in state B. The device reads the keys, performs operations using those keys, then transitions to state B, where those private keys should no longer be accessible.
During the transition from A to B, the device does not scrub the memory.