Memory hygiene is the practice of controlling what an AI system stores, recalls, and retains over time. In agentic or assistant-style systems, memory may include user preferences, prior prompts, summaries, credentials, or task context. Good memory hygiene means storing only what is necessary, separating sensitive data from routine context, setting retention limits, and allowing safe deletion or review.
In cyber security, memory is part of the attack surface. If an attacker can poison memory, they may bias future responses, trigger unsafe actions, or cause the system to reveal information it should not keep. Weak retention can also turn a harmless interaction into a long-lived data exposure. Defenders reduce this risk with least-privilege access, scoped memory, encryption, logging, and human review for important actions. Strong memory hygiene helps keep AI behavior predictable and limits how far a single prompt manipulation can spread.