AI agent hacker breached 100+ sites at $50 each: audit side sites

Hacking a company now costs about as much as a tank of gas. On October 19, Reuters reported that a single Chinese-speaking hacker used AI agents to break into more than 100 companies, most of them e-commerce sites, at an estimated $50 in tokens per successful hack. The AI agent hacker did not need a team. It needed a prompt under 100 characters and a budget.

What actually happened

Per Reuters, based on research by Snorre Fagerland at security firm NorForge:

• The scale. The campaign started September 25 and targeted e-commerce sites in the US, Canada, Australia and Japan. Agents tried more than 1,200 sites and got into over 100. Reuters named Deere, SharkNinja and Cummins among the victims.
• The cost. Fagerland estimated about $5,000 in tokens total, or roughly $50 per breach. The logs point to a mix of Anthropic's Claude Code and DeepSeek. That attribution is NorForge's read of the logs, not a confirmed finding.
• The patience. Successful intrusions took about 23 hours of probing each. In one case the agents found nothing on a large company's main app, so they mapped related infrastructure, found a public control panel, and spent hours of trial and error on a subtle data-processing flaw until the server ran their commands.
• The tool. The operator ran Cairn, an open-source multi-agent platform. Fagerland found the infrastructure while scanning for exposed Cairn instances. Its author says it was not built for hacking.
• The weak spots. SharkNinja said the hit was a standalone site holding product support content. Cummins said it was looking into a site run by a third-party vendor.

Why it matters for your business

Read those two statements again. The main storefront held. The side doors did not. A support microsite, a vendor-run landing page, a staging box, a forgotten admin panel. Nobody watches those, and an agent that probes for 23 hours straight for $50 will find them.

The old math said small shops were not worth a skilled attacker's time. That math is dead. When an attack costs $50, every site with a login or a database is worth a try.

What we do for clients:

• Inventory every hostname. Pull your DNS records and certificate logs. Anything you do not recognize gets an owner or gets shut off.
• Kill public admin panels. Put control panels behind a VPN, an IP allowlist or SSO. Never on the open web.
• Hold vendors to the same bar. A site a vendor runs under your brand is your breach. Put patching and access terms in the contract.
• Patch the boring stuff first. Old plugins and unmaintained subdomains are where agents start.
• Watch for slow probing. Hours of odd requests from one source is the signal. Rate limits and a WAF make the agent's bill climb.

Sources: Reuters via Yahoo News, The Next Web.