CWE-1247: Improper Protection Against Voltage and Clock Glitches

What is Improper Protection Against Voltage and Clock Glitches?

• Overview: Improper Protection Against Voltage and Clock Glitches (CWE-1247) is a hardware vulnerability where a device lacks effective mechanisms to detect and counteract electrical anomalies, like voltage and clock glitches, that could be used to disrupt its normal operation and compromise sensitive data.

• Exploitation Methods:

• Attackers can exploit this vulnerability by generating abrupt changes in voltage or clock signals, causing the device to behave unpredictably or bypass security checks.
• Common attack patterns include fault injection attacks, where glitches are timed precisely to alter device operations, and clock glitching, which manipulates the timing of operations to induce errors.

• Security Impact:

• Direct consequences of successful exploitation can include unauthorized access to secure areas of the device, bypassing authentication checks, or executing arbitrary code.
• Potential cascading effects might involve broader system compromise if the device is part of a network or critical infrastructure, leading to further security breaches.
• Business impact could be severe, including data theft, loss of customer trust, legal liabilities, and financial losses due to compromised systems.

• Prevention Guidelines:

• Specific code-level fixes are not applicable as this is a hardware issue, but software should include checks that validate the integrity of operations.
• Security best practices include designing devices with robust hardware security features, such as sensors and circuits that detect anomalies in voltage and clock signals.
• Recommended tools and frameworks include using secure boot processes, implementing hardware-based access controls, and employing fault-tolerant design patterns in both hardware and firmware.

Corgea can automatically detect and fix Improper Protection Against Voltage and Clock Glitches in your codebase. Try Corgea free today.

Technical Details

Likelihood of Exploit: Not specified

Affected Languages: Not Language-Specific

Affected Technologies: ICS/OT, System on Chip, Power Management Hardware, Clock/Counter Hardware, Sensor Hardware

Vulnerable Code Example

import time

def perform_secure_operation():
    # Simulate a critical operation that requires protection
    print("Performing a critical secure operation...")

def main():
    # Assume an external signal triggers this operation
    perform_secure_operation()

if __name__ == "__main__":
    # Start a simple loop with fixed timing (vulnerable to clock glitches)
    while True:
        main()
        time.sleep(1)  # Fixed delay makes the system vulnerable to clock glitches

Vulnerability Explanation:

• The time.sleep(1) introduces a fixed delay, creating a predictable timing pattern. This predictability can be exploited by an attacker using clock glitching techniques to manipulate the timing of critical operations, potentially bypassing security measures or causing unintended behavior.

How to fix Improper Protection Against Voltage and Clock Glitches?

To protect against voltage and clock glitches:

1. Introduce Randomization: Add random delays or operations to make timing unpredictable, reducing susceptibility to clock-based attacks.
2. Use Hardware-Based Protections: Implement hardware sensors and circuits to detect abnormal voltage or clock signals and trigger protective countermeasures.
3. Integrity Checks: Regularly verify the integrity of the critical operations' execution to ensure they haven't been tampered with.
4. Redundancy and Fallback Mechanisms: Implement redundant checks and fallback mechanisms to maintain operation under attack conditions.

Fixed Code Example

import time
import random

def perform_secure_operation():
    # Perform a critical operation with additional integrity checks
    print("Performing a critical secure operation...")

def main():
    perform_secure_operation()
    # Add a random delay to disrupt predictable timing
    random_delay = random.uniform(0.5, 1.5)
    time.sleep(random_delay)  # Introduces random delay for unpredictability

def perform_integrity_check():
    # Example integrity check to ensure operation hasn't been tampered with
    print("Integrity check passed.")

if __name__ == "__main__":
    while True:
        main()
        perform_integrity_check()  # Regular integrity checks to detect tampering

Fix Explanation:

• Random Delay: By introducing a random delay (random.uniform(0.5, 1.5)), the loop's timing becomes less predictable, making it more difficult for attackers to synchronize glitching attempts with the critical operation.
• Integrity Check: Adding a periodic integrity check ensures that any tampering with the critical operation can be detected promptly.
• Hardware-Based Measures: Although not shown in the code, incorporating hardware solutions to detect and respond to voltage or clock anomalies is strongly recommended for robust security.