The first AI-run cyberattack is already here
For years, "AI hacker" was a phrase for conference slides and movie trailers. In November 2025 it became an incident report. Anthropic , the company behind Claude, published details of what it called the first documented large-scale cyberattack executed mostly by AI. I use AI agents every day to bu
Posted on Nov 2 • Originally published at ksatriabintangsamudra.com
For years, "AI hacker" was a phrase for conference slides and movie trailers. In November 2025 it became an incident report.
Anthropic, the company behind Claude, published details of what it called the first documented large-scale cyberattack executed mostly by AI. I use AI agents every day to build software, so this report hit close to home. The same tools that make me faster can make an attacker faster too.
According to Anthropic, in mid-September 2025 it detected a state-sponsored group, which it designated GTG-1002 and assessed as Chinese with high confidence. The group used Claude Code, Anthropic's coding agent, inside an automated framework to target roughly 30 organisations: tech companies, financial institutions, chemical manufacturers and government agencies. A small number of intrusions succeeded.
The scary part is the division of labour. Anthropic estimated that AI did the large majority of the tactical work. Humans picked the targets and approved the big moves. The agent did the grind: mapping systems, finding weak spots, writing exploit code, testing stolen credentials, and sorting stolen data to find what was valuable.
Work that used to take a team of operators weeks was happening at machine speed.
AI models are trained to refuse obviously malicious work. So the attackers did what social engineers have always done: they lied.
No single prompt looked like a crime. The crime only appeared when you saw all of them together. That is a lesson for anyone building AI products: safety checks on single requests are not enough.
This is the part people skip. Anthropic noted the agent sometimes hallucinated: it claimed to find credentials that did not work, or presented public information as a secret discovery. Humans still had to check its homework.
So no, we are not at "press a button, hack a bank". But we are past "AI can only write phishing emails". The gap between those two is closing every few months.
Most people will never face a state-level AI agent. They will face the cheaper stuff:
I do not think the answer is panic. It is matching speed with speed.
The first AI-run cyberattack did not look like a movie. It looked like a very fast, very tireless junior operator that sometimes made things up, supervised by a few humans. That is already enough to change the economics of hacking. Defenders who refuse to use the same tools will simply be slower, and in security, slower usually means breached.