Missing Write Protection for Parametric Data Values

Opis

The device does not write-protect the parametric data values for sensors that scale the sensor value, allowing untrusted software to manipulate the apparent result and potentially damage hardware or cause operational failure.

Various sensors are used by hardware to detect any devices operating outside of the design limits. The threshold limit values are set by hardware fuses or trusted software such as the BIOS. These limits may be related to thermal, power, voltage, current, and frequency. Hardware mechanisms may be used to protect against alteration of the threshold limit values by untrusted software.

The limit values are generally programmed in standard units for the type of value being read. However, the hardware-sensor blocks may report the settings in different units depending upon sensor design and operation. The raw sensor output value is converted to the desired units using a scale conversion based on the parametric data programmed into the sensor. The final converted value is then compared with the previously programmed limits.

While the limit values are usually protected, the sensor parametric data values may not be. By changing the parametric data, safe operational limits may be bypassed.

Skutki

• Availability

  Quality Degradation; DoS: Resource Consumption (Other)

  Sensor value manipulation, particularly thermal or power, may allow physical damage to occur or disabling of the device by a false fault shutdown causing a Denial-Of-Service.

Zapobieganie

• Architecture and Design

  Access controls for sensor blocks should ensure that only trusted software is allowed to change threshold limits and sensor parametric data.

  Skuteczność: High

Przykłady podatności

• CVE-2017-8252 Kernel can inject faults in computations during the execution of TrustZone leading to information disclosure in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer Electronics Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon IoT, Snapdragon Mobile, Snapdragon Voice and Music, Snapdragon Wearables, Snapdragon Wired Infrastructure and Networking.

Słabość nadrzędna

• CWE-862 Missing Authorization

Pokrewna

• CWE-1299 Missing Protection Mechanism for Alternate Hardware Interface

Kiedy powstaje

• Architecture and Design — The lack of a requirement to protect parametric values may contribute to this weakness.
• Implementation — The lack of parametric value protection may be a cause of this weakness.

Dotyczy

Not Language-Specific, Not OS-Specific, Not Architecture-Specific, Sensor Hardware

Źródła

1. CLKSCREW: Exposing the Perils of Security-Oblivious Energy Management — Adrian Tang, Simha Sethumadhavan, Salvatore Stolfo