VS Code Extension with 9 Million Installs Attacks Developers with Malicious Code

Microsoft has removed two widely-used Visual Studio Code (VS Code) extensions, “Material Theme Free” and “Material Theme Icons Free,” from its marketplace after cybersecurity researchers discovered malicious code embedded within them.

These extensions, developed by Mattia Astorino (also known as equinusocio), had amassed nearly 9 million installations combined, with Astorino’s total extension downloads exceeding 13 million.

Following the removal, users received alerts notifying them that the extensions had been disabled for security reasons.

The investigation revealed that the malicious code was likely introduced through a compromised dependency or during a recent update.

This suggests a possible supply chain attack or unauthorized access to the developer’s account.

Researchers noted that themes like these should typically consist of static JSON files and not execute any code, making the presence of obfuscated JavaScript in the extensions a significant red flag.

Malicious Intent Uncovered

The malicious behavior was initially flagged by cybersecurity experts Amit Assaraf and Itay Kruk, who specialize in detecting harmful VS Code extensions.

The analysis revealed heavily obfuscated JavaScript code in the extensions, which included references to usernames and passwords.

Although the exact purpose of this code remains unclear due to its complexity, its presence was sufficient to warrant immediate action by Microsoft.

Astorino has denied any intentional wrongdoing, attributing the issue to an outdated Sanity.io dependency used since 2016.

He criticized Microsoft for not notifying him before removing the extensions, claiming that fixing the dependency would have been a quick process.

However, Microsoft’s independent analysis corroborated the researchers’ findings, leading to the removal of all extensions associated with Astorino from the marketplace.

Potential Risks and Recommendations

The incident underscores the risks posed by malicious components in software supply chains.

Threat actors often exploit open-source platforms like VS Code Marketplace to distribute harmful code under the guise of legitimate extensions.

In this case, developers who installed these compromised extensions may have unknowingly exposed sensitive information or systems to potential breaches.

To mitigate risks, developers are advised to uninstall all extensions published by equinusocio, including:

• equinusocio.moxer-theme
• equinusocio.vsc-material-theme
• equinusocio.vsc-material-theme-icons
• equinusocio.vsc-community-material-theme
• equinusocio.moxer-icons.

This incident highlights the importance of scrutinizing third-party dependencies and maintaining robust supply chain security practices.

Developers should regularly audit their tools and avoid extensions with suspicious or obfuscated code.

Collect Threat Intelligence on the Latest Malware and Phishing Attacks with ANY.RUN TI Lookup -> Try for free

Keep your files stored safely and securely with the SanDisk 2TB Extreme Portable SSD. With over 69,505 ratings and an impressive 4.6 out of 5 stars, this product has been purchased over 8K+ times in the past month. At only $129.99, this Amazon’s Choice product is a must-have for secure file storage.

Help keep private content private with the included password protection featuring 256-bit AES hardware encryption. Order now for just $129.99 on Amazon!

Help Power Techcratic’s Future – Scan To Support

If Techcratic’s content and insights have helped you, consider giving back by supporting the platform with crypto. Every contribution makes a difference, whether it’s for high-quality content, server maintenance, or future updates. Techcratic is constantly evolving, and your support helps drive that progress.

As a solo operator who wears all the hats, creating content, managing the tech, and running the site, your support allows me to stay focused on delivering valuable resources. Your support keeps everything running smoothly and enables me to continue creating the content you love. I’m deeply grateful for your support, it truly means the world to me! Thank you!