From Phishing to LLMjacking: Threat Actors Targeting Cloud Billing Accounts for LLM Usage

The Wiz Customer Incident Response Team (CIRT) has investigated a rising threat pattern in cloud environments: threat actors hijacking cloud billing accounts to fund unauthorized AI usage. Threat actors are not only using AI as a tool to conduct attacks, they are also compromising victim environments solely to abuse their finances for mass Large Language Model (LLM) execution, incurring hundreds of thousands of dollars in AI API charges. Wiz CIRT has investigated multiple intrusions demonstrating this pattern, with this blogpost focusing specifically on campaigns targeting Google Cloud Platform (GCP) infrastructure. In these attacks, threat actors compromised privileged GCP user credentials and linked external, attacker-controlled GCP projects directly to the victim's internal billing accounts. Because the AI workloads were processed in foreign projects, prompt contents and model outputs…