Anthropic
Detecting and Countering Misuse of AI: August 2025
'Vibe Hacking': How Cybercriminals Used Claude Code to Scale a Data Extortion Operation
Threat Actors' Latest Trick: Exploiting AI Capabilities
We recently disrupted a sophisticated cybercriminal operation that used Claude Code to commit large-scale theft and extortion of personal data.
The actor targeted at least 17 distinct organizations, including in healthcare, the emergency services, and government and religious institutions.
Rather than encrypting the stolen information with traditional ransomware, the actor threatened to expose the data publicly in order to attempt to extort victims into paying ransoms that sometimes exceeded $500,000.
The actor used AI to automate reconnaissance, harvesting victims' credentials, and penetrating networks.
Claude Code was used to make both tactical and strategic decisions, such as deciding which data to exfiltrate, and how to craft psychologically targeted extortion demands.
Claude analyzed the exfiltrated financial data to determine appropriate ransom amounts, and generated visually alarming ransom notes that were displayed on victim machines.
Implications: Evolution in AI-Assisted Cybercrime
This represents an evolution in AI-assisted cybercrime. Agentic AI tools are now being used to provide both technical advice and active operational support for attacks that would otherwise have required a team of operators.
This makes defense and enforcement increasingly difficult, since these tools can adapt to defensive measures, like malware detection systems, in real time.
Our Response: Banning Accounts and Developing New Detection Tools
We banned the accounts in question as soon as we discovered this operation.
We have also developed a tailored classifier (an automated screening tool), and introduced a new detection method to help us discover activity like this as quickly as possible in the future.
To help prevent similar abuse elsewhere, we have also shared technical indicators about the attack with relevant authorities.
Remote Worker Fraud: How North Korean IT Workers Are Scaling fraudulent Employment with AI
A Sophisticated Scam: Using Claude to Secure Remote Employment Positions
We discovered that North Korean operatives had been using Claude to fraudulently secure and maintain remote employment positions at US Fortune 500 technology companies.
This involved using our models to create elaborate false identities with convincing professional backgrounds, complete technical and coding assessments during the application process, and deliver actual technical work once hired.
Implications: A Fundamental New Phase for Employment Scams
North Korean IT workers previously underwent years of specialized training prior to taking on remote technical work, which made the regime’s training capacity a major bottleneck.
Our Response: Improving Tools and Sharing Findings
We immediately banned the relevant accounts, and have since improved our tools for collecting, storing, and correlating the known indicators of this scam.
We’ve also shared our findings with the relevant authorities, and we’ll continue to monitor for attempts to commit fraud using our services.
The Threat: A Cybercriminal Using Claude to Develop Ransomware
A New Level of Malware Development: Using AI to Create Ransomware
A cybercriminal used Claude to develop, market, and distribute several variants of ransomware, each with advanced evasion capabilities, encryption, and anti-recovery mechanisms.
The ransomware packages were sold on internet forums to other cybercriminals for $400 to $1200 USD.
Implications: The Dependence on AI
This actor appears to have been dependent on AI to develop functional malware. Without Claude’s assistance, they could not implement or troubleshoot core malware components, like encryption algorithms, anti-analysis techniques, or Windows internals manipulation.
Our Response: Banning Accounts and Alerting Partners
We have banned the account associated with this operation, and alerted our partners.
We’ve also implemented new methods for detecting malware upload, modification, and generation, to more effectively prevent the exploitation of our platform in the future.
Conclusion: A Growing Concern
In each of the cases described above, the abuses we’ve uncovered have informed updates to our preventative safety measures.
We have also shared details of our findings, including indicators of misuse, with third-party safety teams.
The growth of AI-enhanced fraud and cybercrime is particularly concerning to us, and we plan to prioritize further research in this area.
We’re committed to continually improving our methods for detecting and mitigating these harmful uses of our models.