Critical Malicious Code Vulnerability in format-defaults Package
Summary
MAL-2026-959: Malicious code in format-defaults (npm). Affected versions are not published. No fix is published. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
The format-defaults package is a Node.js library used in npm ecosystems to manage default formatting options for various applications. It is designed to streamline the configuration process for developers by providing a set of predefined formatting rules. However, this package has been identified as containing malicious code, which poses significant security risks to any system utilizing it.
Vulnerability Detail
The vulnerability stems from the presence of embedded malicious code within the format-defaults package. This code can compromise the integrity of any computer that has the package installed, allowing unauthorized access to sensitive information such as secrets and keys. The origin of this vulnerability is linked to a malicious actor who has injected harmful code into the package, making it a severe threat to users and their systems.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall format-defaultsIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
As a workaround, you can temporarily avoid using the format-defaults package by replacing its functionality with alternative libraries or custom code that does not pose a security risk. Ensure to audit your dependencies regularly to avoid similar vulnerabilities.
Conclusion
The format-defaults package has been identified as containing malicious code, posing a significant risk to systems that utilize it. Immediate action is required to remove the package and secure any sensitive information. Regular monitoring of dependencies is essential to prevent future vulnerabilities.
See every vulnerability recorded for format-defaults →
FAQ
You should immediately remove the package and rotate any sensitive information stored on your system.
You can use Vulert's playground at Vulert Scanner to check if your application is affected without needing to sign up.
Failing to address this vulnerability can lead to unauthorized access to your system, data breaches, and potential loss of sensitive information.
Yes, Vulert provides a service that monitors your package-lock.json file for open-source vulnerabilities in real-time.
It is advisable to avoid using the format-defaults package altogether until a verified, secure version is released.
