Malicious Code Detected in pdfjs-dist-fourth: Version 10.0.33 Vulnerability
Summary
MAL-2026-1257: Malicious code in pdfjs-dist-fourth (npm). Affects pdfjs-dist-fourth versions 10.0.33. No fix is published. How to fix ↓
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Background
pdfjs-dist-fourth is an npm package that provides a JavaScript library for rendering PDF documents in web applications. It is widely used for displaying PDF files in a user-friendly manner. However, version 10.0.33 of this package has been flagged for containing malicious code, which poses a significant risk to users and their applications.
Vulnerability Detail
The vulnerability in pdfjs-dist-fourth arises from its communication with a domain associated with malicious activities and the execution of commands linked to harmful behavior. This can lead to unauthorized access, data breaches, or the execution of arbitrary code within the user's environment, potentially compromising the integrity and security of the application.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall pdfjs-dist-fourthIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary workaround, you can remove the pdfjs-dist-fourth package from your project until a secure version is confirmed. You can do this by executing the following command: npm uninstall pdfjs-dist-fourth.
Conclusion
The discovery of malicious code in pdfjs-dist-fourth version 10.0.33 highlights the importance of maintaining secure dependencies in software development. Users are advised to update or remove the affected package to mitigate potential risks.
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FAQ
The package communicates with a domain linked to malicious activities and executes harmful commands, posing security risks.
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Consider removing the package as a temporary measure until a secure version is available.
While specific exploits have not been detailed, the nature of the malicious behavior suggests potential for unauthorized access and data breaches.
Regularly check for updates on your packages and utilize tools like Vulert to monitor vulnerabilities in real-time.
