Improper Protection Against Voltage and Clock Glitches
The device does not contain or contains incorrectly implemented circuitry or sensors to detect and mitigate voltage and clock glitches and protect sensitive information or software contained on the device.
Description
A device might support features such as secure boot which are supplemented with hardware and firmware support. This involves establishing a chain of trust, starting with an immutable root of trust by checking the signature of the next stage (culminating with the OS and runtime software) against a golden value before transferring control. The intermediate stages typically set up the system in a secure state by configuring several access control settings. Similarly, security logic for exercising a debug or testing interface may be implemented in hardware, firmware, or both. A device needs to guard against fault attacks such as voltage glitches and clock glitches that an attacker may employ in an attempt to compromise the system.
Demonstrations
The following examples help to illustrate the nature of this weakness and describe methods or techniques which can be used to mitigate the risk.
Note that the examples here are by no means exhaustive and any given weakness may have many subtle varieties, each of which may require different detection methods or runtime controls.
Example One
Below is a representative snippet of C code that is part of the secure-boot flow. A signature of the runtime-firmware image is calculated and compared against a golden value. If the signatures match, the bootloader loads runtime firmware. If there is no match, an error halt occurs. If the underlying hardware executing this code does not contain any circuitry or sensors to detect voltage or clock glitches, an attacker might launch a fault-injection attack right when the signature check is happening (at the location marked with the comment), causing a bypass of the signature-checking process.
...
if (signature_matches) // <-Glitch Here
{
load_runtime_firmware();
}
else
{
do_not_load_runtime_firmware();
}
...After bypassing secure boot, an attacker can gain access to system assets to which the attacker should not have access.
If the underlying hardware detects a voltage or clock glitch, the information can be used to prevent the glitch from being successful.See Also
Weaknesses in this category are related to improper check or handling of exceptional conditions.
Weaknesses in this category are related to concerns of physical access.
Weaknesses in this category are related to the "External Physical Systems" category from the SEI ETF "Categories of Security Vulnerabilities in ICS" as published in Ma...
This view (slice) covers all the elements in CWE.
This view (slice) displays only weakness base elements.
Common Weakness Enumeration content on this website is copyright of The MITRE Corporation unless otherwise specified. Use of the Common Weakness Enumeration and the associated references on this website are subject to the Terms of Use as specified by The MITRE Corporation.