3AM ransomware used a hybrid human-AI approach in a September 2026 compromise of a UK school estate, according to research published by Bitdefender on November 3, 2026. The research blog attributes the attack to a 3AM ransomware affiliate. The attack ran from September 10 to 19, 2026, and resulted in the attackers encrypting 37 machines.
Bitdefender said parts of the post-compromise activity were carried out by a human operator at the keyboard, while other parts behaved like an AI agent. The researchers described the attack as "the first case of this kind that we have documented in Europe."
The researchers could not determine how the attacker gained initial access to the school estate. The first recorded activity began on September 10, when the attacker accessed credentials stored in the estate's backup infrastructure and decrypted them with the Windows Data Protection API.
From September 12 to 13, the attacker tested connections to other hosts and sent commands to the Windows Management Instrumentation (WMI) service using stolen administrator credentials. Bitdefender said the timing of retries, with a complete rewrite arriving as fast as minor changes, indicates the commands were written by an AI agent. Longer gaps between later tasks, of two to 16