Misconfigured cloud instances have once again enabled cybercriminals to steal sensitive data, including credentials, API keys, and proprietary source code. This time, numerous Amazon Web Services (AWS) users fell victim, highlighting a lack of understanding regarding the shared responsibility model in cloud infrastructure.

Discovery of Vulnerabilities

Independent security researchers Noam Rotem and Ran Loncar uncovered open flaws in public websites in August 2024. These flaws could be exploited to access sensitive customer data, infrastructure credentials, and proprietary source code.

Data Exploitation and Sale on Telegram

Further investigation revealed that French-speaking threat actors, potentially linked to hacker groups Nemesis and ShinyHunters, scanned "millions of websites" for vulnerabilities. By exploiting these flaws, they harvested an array of sensitive information, including:

• AWS customer keys and secrets
• Database credentials and data
• Git repository data and source code
• SMTP credentials for email sending
• API keys for services like Twilio, Binance, and SendGrid
• SSH credentials
• Cryptocurrency-related keys and mnemonics
• Other sensitive access data

The stolen data was sold via a private Telegram channel, reportedly earning "hundreds of euros per breach." Investigators noted that the perpetrators might need the funds for legal defense once apprehended.

Investigation and Response

Rotem and Loncar traced the incident to specific individuals and reported their findings to Israel's Cyber Directorate and AWS Security. The researchers stated: "Our investigation has identified the names and contact information of several individuals behind this incident. This could help in further actions against the perpetrators."

AWS promptly took action to mitigate risks and emphasized that the vulnerability stemmed from user-side misconfigurations rather than AWS systems: "The AWS Security team emphasized that this operation does not pose a security issue for AWS, but rather is on the customer side of the shared responsibility model – a statement we fully agree with," vpnMentor reported.

The Shared Responsibility Model

The shared responsibility model in cloud computing divides security responsibilities between the cloud service provider and the customer. AWS ensures the security of its infrastructure, while customers are responsible for securely configuring and managing their data and applications.

Irony in Misconfiguration

Ironically, the stolen data was discovered in an unprotected AWS S3 bucket—another misconfiguration. According to the researchers: "The data collected from the victims was stored in an S3 bucket, which was left open due to a misconfiguration by the owner. The S3 bucket was used as a 'shared disk' between the members of the attack group, based on the source code of the tools they used."

Lessons for Cloud Security

Cybersecurity experts emphasize that cloud misconfigurations remain a leading cause of data breaches. Organizations must take proactive steps to secure their cloud environments:

• Implement strict access controls and regular audits of cloud configurations.
• Use tools to detect misconfigurations and vulnerabilities in real-time.
• Educate employees about the shared responsibility model and best practices for cloud security.

This incident underscores the critical need for customers to take their share of responsibility in safeguarding sensitive data and highlights the risks of negligence in cloud security practices.