CyberGlossary

Vulnerabilities

Fault Injection

Also known as: Glitching attack, Fault attack

Definition

A class of physical or logical attacks that deliberately induce abnormal conditions in hardware or software to bypass security checks or leak secrets.

Fault injection deliberately disturbs the normal operation of a system — through voltage glitches, electromagnetic pulses, laser beams on a chip, clock manipulation, or malformed software inputs — to cause incorrect behaviour the attacker can exploit. Typical goals include skipping authentication checks, corrupting cryptographic computations to leak keys (differential fault analysis), or escaping secure boot. Both embedded devices (smart cards, TPMs, automotive ECUs) and high-value software are targets. Countermeasures include redundant computations, fault-detection sensors, randomised execution, error-correcting memory, secure-element shielding, and defensive programming that double-checks security decisions.

Examples

  • Voltage glitching a smart card to skip a PIN verification branch.
  • Differential fault analysis on AES to recover a key from a corrupted ciphertext.

Related terms