data-poisoning

Data poisoning and backdoors: attacking a model through what it eats Lesson

Data poisoning is an attack that corrupts a model by tampering with its training data rather than its code, and a backdoor is the sharpest form: a model that behaves perfectly until it sees a secret trigger. Anthropic and the UK AI Safety Institute found in 2025 that just 250 poisoned documents compromised models from 600 million to 13 billion parameters alike, which means scale does not dilute the threat.