## TL;DR
Adversarial Machine Learning studies how AI systems can be fooled — and defended. Tiny perturbations invisible to humans can cause state-of-the-art models to misclassify with high confidence. Building robust AI requires understanding the attack surface and engineering defenses.
## Core Explanation
Adversarial attacks: (1) Evasion attacks — add imperceptible perturbation ε to input x such that f(x+ε) ≠ f(x). FGSM (Fast Gradient Sign Method): x' = x + ε·sign(∇_x L). PGD (Projected Gradient Descent) iterates FGSM within L∞ ball. Physical attacks: printed adversarial patches on objects fool real-world computer vision. (2) Poisoning attacks — inject malicious samples into training data to create backdoors. (3) Privacy attacks — extract training data (membership inference) or reconstruct inputs (model inversion).
## Detailed Analysis
Defense taxonomy: (1) Adversarial training — augment training with adversarial examples (most effective but computationally expensive); (2) Certified defenses — provide mathematical guarantees of robustness within perturbation bounds (randomized smoothing, interval bound propagation); (3) Detection methods — identify adversarial inputs at inference (feature squeezing, MagNet); (4) Input preprocessing — JPEG compression, total variation minimization to remove perturbations. 2025 trend: multimodal adversarial attacks combining visual, text, and audio modalities. NIST emphasizes that no defense is universally effective — defense-in-depth and red teaming are essential. ICCV 2025 featured adversarial vulnerability exploration in vision-language-action models for robotics.
## Further Reading
- Adversarial Robustness Toolbox (IBM ART)
- CleverHans Library (Google/TensorFlow)
- NIST AI Risk Management Framework