COMMON WEAKNESS ENUMERATIONIncomplete

CWE-1319

Improper Protection against Electromagnetic Fault Injection (EM-FI)

The device is susceptible to electromagnetic fault injection attacks, causing device internal information to be compromised or security mechanisms to be bypassed.

Abstraction

Base

Structure

Simple

Likelihood of Exploit

Medium

Understand the problem

What is the problem?

The device is susceptible to electromagnetic fault injection attacks, causing device internal information to be compromised or security mechanisms to be bypassed.

Extended description

Electromagnetic fault injection may allow an attacker to locally and dynamically modify the signals (both internal and external) of an integrated circuit. EM-FI attacks consist of producing a local, transient magnetic field near the device, inducing current in the device wires. A typical EMFI setup is made up of a pulse injection circuit that generates a high current transient in an EMI coil, producing an abrupt magnetic pulse which couples to the target producing faults in the device, which can lead to: - Bypassing security mechanisms such as secure JTAG or Secure Boot - Leaking device information - Modifying program flow - Perturbing secure hardware modules (e.g. random number generators)

Root cause

How and when does the problem arise?

Lifecycle phase

Architecture and Design

Lifecycle phase

Implementation

Risk

What does successful exploitation lead to?

Modify MemoryRead MemoryGain Privileges or Assume IdentityBypass Protection MechanismExecute Unauthorized Code or Commands

Affected security scopes: Confidentiality, Integrity, Access Control, Availability

Defence

How is it prevented and fixed?

Architecture and Design · Implementation

Defence to apply across several lifecycle phases

Detail
- 1. Redundancy - By replicating critical operations and comparing the two outputs can help indicate whether a fault has been injected. - 2. Error detection and correction codes - Gay, Mael, et al. proposed a new scheme that not only detects faults injected by a malicious adversary but also automatically corrects single nibble/byte errors introduced by low-multiplicity faults. - 3. Fail by default coding - When checking conditions (switch or if) check all possible cases and fail by default because the default case in a switch (or the else part of a cascaded if-else-if construct) is used for dealing with the last possible (and valid) value without checking. This is prone to fault injection because this alternative is easily selected as a result of potential data manipulation [REF-1141]. - 4. Random Behavior - adding random delays before critical operations, so that timing is not predictable. - 5. Program Flow Integrity Protection - The program flow can be secured by integrating run-time checking aiming at detecting control flow inconsistencies. One such example is tagging the source code to indicate the points not to be bypassed [REF-1147]. - 6. Sensors - Usage of sensors can detect variations in voltage and current. - 7. Shields - physical barriers to protect the chips from malicious manipulation.