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VS Code Extensions Leak Sensitive Secrets, Exposing Users to Supply Chain Attacks

Updated October 16, 2025 at 10:13 PM3 sources

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Researchers discovered that over 550 sensitive secrets were inadvertently leaked through more than 500 Visual Studio Code (VS Code) extensions available on both the VS Code and Open VSX marketplaces. These secrets included access and authorization tokens, credentials, API keys, encryption keys, and certificates, which are critical for securing access to various platforms and services. The investigation, conducted by Wiz Security, revealed that the leaked secrets spanned 67 categories, with the majority falling into three main groups: generative AI platforms, high-risk professional platforms such as AWS, GCP, Auth0, and GitHub, and databases like MongoDB and Postgres. Notably, more than 100 of the exposed secrets would have allowed attackers to update the affected extensions themselves. Because VS Code automatically updates extensions, this created a significant risk that attackers could deploy malicious updates to a large user base without user intervention. Wiz Security estimated that, had these vulnerabilities been exploited, malware could have been pushed to approximately 150,000 users in a single attack. The risk was not limited to code-heavy extensions; even theme extensions, which are often perceived as harmless, were found to be capable of introducing malware. The research highlighted that some internal extensions, such as those published by large corporations for internal use, were inadvertently made public, further increasing the attack surface. Vendor-specific extensions, commonly used for convenience, were identified as particularly attractive targets for attackers due to their potential for targeted exploitation. Microsoft was notified of the findings and worked with the researchers to address the issues and mitigate the risks. The incident underscores the importance of rigorous security practices in extension development and the need for continuous monitoring of third-party code in software supply chains. The exposure of secrets in widely used development tools like VS Code demonstrates how supply chain vulnerabilities can have far-reaching consequences. Organizations are advised to audit their use of extensions, restrict unnecessary permissions, and ensure that sensitive credentials are never hardcoded or exposed in public repositories. The case also serves as a warning about the risks of publishing internal tools to public marketplaces, as this can inadvertently expose sensitive infrastructure to external threats. The findings have prompted calls for improved vetting processes for extensions and greater awareness among developers about the risks of credential leakage. This incident is a stark reminder that even seemingly minor oversights in software development can lead to large-scale security incidents affecting tens of thousands of users. The potential for automated malware deployment through compromised extensions highlights the evolving nature of supply chain threats in the software ecosystem. Security researchers continue to monitor the situation and recommend best practices for extension security to prevent similar incidents in the future.

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