Cybercriminals looking to abuse the power of generative AI to build phishing campaigns and sophisticated malware can now purchase easy access to them from underground marketplaces as large numbers of threat actors are putting stolen GenAI credentials up for sale every day.

Hackers are selling usernames and passwords of approximately 400 individual GenAI accounts per day, according to an eSentire study.

“Cybercriminals are advertising the credentials on popular Russian Underground Markets, which specialize in everything from malware to infostealers to crypters,” said eSentire researchers in the report. “Many of the GenAI credentials are stolen from corporate end-users’ computers when they get infected with an infostealer.”

A Stealer Log, which refers to all the information an infostealer retrieves from the victim machines including the GenAI credentials, is currently being sold at $10 each on the underground markets.

LLM Paradise is among the most used

One of the most prominent underground markets that was found facilitating the exchange of GenAI credentials was LLM Paradise, researchers said.

“The threat actor running this market had a knack for marketing jargon, naming their store LLM Paradise and touting stolen GPT-4 and Claude API keys with ads reading: ‘The Only Place to get GPT-4 APIKEYS for unbeatable prices,’” researchers said.

The threat actor advertised GPT-4 or Claude API keys starting at only $15 each, while typical prices for various OpenAI models run between $5 and $30 per million tokens utilized, the researchers added.

LLM Paradise, however, couldn’t sustain itself for longer and, for unknown reasons, shut down its services recently. However, threat actors went around the snag and are still operating some ads for stolen GPT-4 API keys on TikTok, published since before the marketplace was shuttered.

Other than the GPT-4 and Claude APIs, other credentials put up for sale on LLM Paradise-like marketplaces include those for Quillbot, Notion, Huggingface, and Replit.

Credentials can be used for phishing, malware and breaches

eSentire researchers said the stolen credentials have greater value at the hands of cybercriminals for their multifold returns. “Threat actors are using popular AI platforms to create convincing phishing campaigns, develop sophisticated malware, and produce chatbots for their underground forums,” they said.

Additionally, they can be used to access an organization’s corporate GenAI accounts which further allows access to customers’ personal and financial information, proprietary intellectual property, and personally identifiable information.

The hacked credentials can also allow access to data restricted to corporate customers only, thereby affecting GenAI platform providers too. OpenAI was found to be the most affected with over 200 OpenAI credentials posted for sale per day.

Regular monitoring of employee’s GenAI usage, having GenAI providers implement WebAuthn with MFA options, including passkey or password best practices for GenAI authentication, and using dark web monitoring services to identify stolen credentials are a few steps corporate users can follow to defend against GenAI attacks.