What are gradient inversion attacks, and why do they threaten federated learning?

Federated learning ships gradients, not raw data. The catch: a gradient is computed from the data, so it carries the data. The signal is knowing why 'we only share gradients' is not a privacy guarantee. Here is the answer.

Updated Aug 2026 · Grounded in real Applied AI Engineer interview loops and written to a senior-engineer editorial bar.