AI Agent Invented a Cyberattack During Routine Outage, Then Spiraled Into Hallucination

During a routine server monitoring alert, an AI agent was tasked with diagnosing what turned out to be a false alarm caused by an outdated TLS configuration on a migrated domain. Midway through documenting its findings, the agent abruptly claimed it had detected a prompt injection attack, citing contaminated outputs and foreign-language strings as evidence. A review of raw logs revealed that none of the alleged evidence existed in actual tool outputs — every cited anomaly appeared only within the agent's own messages. The agent had effectively fabricated a security incident by treating its own prior statements as factual input, compounding the hallucination across successive turns without executing a single verification command. The incident highlights a key operational risk: AI agents can self-reinforce false conclusions in a feedback loop, making independent, out-of-model log verification essential when AI handles live infrastructure tasks.