A hacker’s AI agents broke into 100+ websites for about $50 each. Here’s how to protect yours

On Monday, Reuters reported that a single hacker broke into the websites of more than 100 companies, including farm equipment maker Deere, appliance company SharkNinja, and engine manufacturer Cummins. But the hacker did almost none of the work: AI agents spent hours probing the sites on their own.

The researcher who found the campaign, Snorre Fagerland of the security firm NorForge, published his findings the same day. They show how cheap a break-in has become, and why a small business’s website is now worth an attacker’s time.

What the researcher found

Fagerland was scanning the internet for exposed control panels of Cairn, an open-source tool that directs AI agents toward a goal. He found more than 20 that were likely being used for attacks.

The hacker in the Reuters story wrote the agents’ instructions in fewer than 100 Chinese characters, pointing them at online stores in the U.S., Canada, Japan, and Australia. Their job was to find a way to run their own code on each site, through weak spots such as login forms and file uploads, and to leave a back door behind. Reuters reported that they had tried more than 1,200 sites.

Successful break-ins took a little under 23 hours on average. In one case, the agents found nothing wrong with a big company’s main application, so they dug up a related control panel, spotted a subtle flaw in how it handled data, and, by their own account, tricked the server into running their commands. “It’s not script kiddie stuff,” Fagerland told Reuters.

NorForge estimates that an average attempt used about $5 in AI costs and that roughly one in 10 succeeded, though it stresses the numbers are rough. Fagerland put the campaign at about $5,000, or around $50 per successful hack.

Deere said it saw “no indication that sensitive information was accessed.” SharkNinja said a standalone support site was hit, and Cummins said it was looking into a possible attack on a site run by one of its vendors.

Why a small business should care

Automated attacks aren’t new, but they mostly tried known, simple flaws. Finding a subtle way in took a skilled person’s time, and that time mostly went to bigger targets. At about $50 a break-in, almost any online business is worth a try. NorForge says one group’s targets were “a mix of smaller e-commerce sites and very large US-based commercial platforms,” and Reuters reports that two smaller businesses acknowledged being compromised.

It isn’t a one-off. In September, the security firm Gambit reported that an attacker using AI agents, Cairn among them, had compromised at least 27 companies and taken more than 600,000 credit card records from two of them.

If your business in Dothan, Enterprise, or anywhere in the Wiregrass takes orders, bookings, or payments online, assume AI agents will test your site.

Five ways to protect your site

1. List everything you have online. Include your website, online store, booking and payment pages, customer portals, admin pages, and any site a vendor runs for you. When a main site held up, the agents went looking for related systems.
2. Keep the software updated. Ask whoever maintains your site how quickly security updates go in. Gambit’s attacker picked shops with custom code, assuming they were more likely to be vulnerable, so a custom-built site needs checkups too.
3. Close the easy doors. Turn on two-step sign-in, remove old accounts and unused plugins, switch off forms and file uploads you don’t need, and keep admin panels off the public internet where you can.
4. Keep backups somewhere else, and test them. In Gambit’s report, an agent’s cleanup routine at a bicycle retailer deleted 180 database tables, including backups the retailer’s own administrators had made.
5. Protect your own AI tools. These attackers were found because they left their dashboards open to the internet, exposing what NorForge calls “literally hundreds of secrets,” including account credentials and API keys. If you connect AI tools to your systems, keep their dashboards private and their keys locked away.

Where we can help

Most of these steps belong to whoever runs your website. We work on the AI side: our AI strategy and training service includes an AI use policy and an independent look at the AI tools being pitched to you, including where the risks are. For the risks inside your own team, see breaches tied to shadow AI doubled this year.

Sources

• NorForge: Inside Cairn: Open Windows into massive AI-Driven Cyber Operations, October 19, 2026
• Reuters, via Yahoo News: How one hacker used AI agents and a few thousand dollars to break into scores of sites, October 19, 2026
• Gambit Security: AI Agents Are Hacking Online Retailers for $25 a Company, September 22, 2026