CWE-1256: Improper Restriction of Software Interfaces to Hardware Features

Description

The product provides software-controllable device functionality for capabilities such as power and clock management, but it does not properly limit functionality that can lead to modification of hardware memory or register bits, or the ability to observe physical side channels.

It is frequently assumed that physical attacks such as fault injection and side-channel analysis require an attacker to have physical access to the target device. This assumption may be false if the device has improperly secured power management features, or similar features. For mobile devices, minimizing power consumption is critical, but these devices run a wide variety of applications with different performance requirements. Software-controllable mechanisms to dynamically scale device voltage and frequency and monitor power consumption are common features in today's chipsets, but they also enable attackers to mount fault injection and side-channel attacks without having physical access to the device. Fault injection attacks involve strategic manipulation of bits in a device to achieve a desired effect such as skipping an authentication step, elevating privileges, or altering the output of a cryptographic operation. Manipulation of the device clock and voltage supply is a well-known technique to inject faults and is cheap to implement with physical device access. Poorly protected power management features allow these attacks to be performed from software. Other features, such as the ability to write repeatedly to DRAM at a rapid rate from unprivileged software, can result in bit flips in other memory locations (Rowhammer, [REF-1083]). Side channel analysis requires gathering measurement traces of physical quantities such as power consumption. Modern processors often include power metering capabilities in the hardware itself (e.g., Intel RAPL) which if not adequately protected enable attackers to gather measurements necessary for performing side-channel attacks from software.

Potential Impact

Demonstrative Examples

Continuously writing the same value to the same address causes the value of an adjacent location to change value.

Redesign the RAM devices to reduce inter capacitive coupling making the Rowhammer exploit impossible.

Mitigations & Prevention

Detection Methods

• Manual Analysis — Perform a security evaluation of system-level architecture and design with software-aided physical attacks in scope.
• Automated Dynamic Analysis Moderate — Use custom software to change registers that control clock settings or power settings to try to bypass security locks, or repeatedly write DRAM to try to change adjacent locations. This can be effective in extracting or changing data. The drawback is that it cannot be run before manufacturing, and i

Real-World CVE Examples

Related Weaknesses