Stolen AI Keys Ran Up $1 Million in Bills, Google Says

Criminals who steal companies’ AI access are running up bills of more than $100,000 a day, and at some firms the total reached $1 million before anyone shut them out. That is the headline figure from a new Google report on a crime called LLMjacking.

The report, published on 2 November by Google Threat Intelligence Group and its incident-response arm Mandiant, covers attacks Mandiant handled in 2026. Victims were in finance, retail, technology and transport across North America, South America and Asia Pacific.

What LLMjacking is

A large language model (LLM) is the kind of AI behind chatbots. Companies pay for it by usage, through API keys, which work like passwords that let software talk to the model. LLMjacking means stealing that access and using it, or selling it, while the victim pays the bill.

Google compares it with cryptojacking, where hackers quietly use someone else’s computers to mine cryptocurrency. The difference is speed. Cryptojacking drains resources slowly. LLMjacking “can generate large spikes in fraudulent cloud charges in a matter of hours”, the report says.

How the keys get stolen

The most common way in was stolen or exposed cloud logins, including keys left in public GitHub code. One group tested stolen keys with tiny requests asking for a single word of output, so the checks would not set off alarms. Another built a fake sign-up page that tricked staff into pasting a live access token, which let the attackers skip passwords and two-factor checks.

Once inside, attackers switched on AI services the company had never used and created extra keys. Request volumes could then jump past 1,000 a second, BleepingComputer reported, and the AI provider simply logs it as normal paid use.

The $60 ‘unlimited’ plan

Much of the stolen access is resold through what Google calls “LLM Mixers”, services that pool stolen keys and sell cheap AI access. One, called Jet Night, made more than 500,000 AI calls in under eight hours on one victim’s keys and passed on nearly $1 million in costs. It sells an unlimited plan for about $60 a month. Google says a comparable legitimate service would usually cost $100 to $250, and believes Jet Night only makes money because it runs on stolen keys.

Google’s advice for companies is basic: rotate keys automatically, scan code for leaked secrets, give accounts only the permissions they need, and set spending caps and alerts on AI services. It also flags a flaw, CVE-2026-40217, in LiteLLM, a popular tool for routing AI traffic, which one group used to turn ordinary keys into admin access.

Why it matters

AI bills are now big enough to be worth stealing. For readers, the lesson is simple: an AI deal that looks far cheaper than the official price may be paid for by someone else’s stolen account. Companies that pay for AI, and reward people for finding its security bugs, now need spending limits as much as passwords.