Malicious Code Vulnerability in is-number-object Package
Summary
MAL-2025-6526: Malicious code in is-number-object (PyPI). Affects is-number-object versions 1.0.8. No fix is published. How to fix ↓
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Background
The is-number-object package is a utility library available on PyPI that is designed to determine if a given value is a number object. It is commonly used in JavaScript applications to validate data types. However, this package has been identified to contain malicious code, which poses a significant risk to users who integrate it into their projects.
Vulnerability Detail
The vulnerability in the is-number-object package stems from the inclusion of malicious code in version 1.0.8. This code can potentially compromise the security of applications that utilize the package, leading to unauthorized access or data manipulation. The malicious code was discovered by ReversingLabs, indicating that the package may have been tampered with or intentionally designed to harm users.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall is-number-objectIf 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 avoid using the is-number-object package altogether and implement your own number validation logic. For example, you can use the following code snippet to check if a value is a number: 'def is_number(value): return isinstance(value, (int, float))'.
Conclusion
The is-number-object package has been found to contain malicious code that poses a security risk to users. It is crucial to update to a patched version or implement workarounds to mitigate potential threats. Regular monitoring of dependencies using tools like Vulert can help maintain application security.
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FAQ
The is-number-object package is a utility library that checks if a given value is a number object, primarily used in JavaScript applications.
The vulnerability was discovered by ReversingLabs, which identified the presence of malicious code in version 1.0.8 of the package.
Using the compromised package can lead to unauthorized access, data manipulation, and other security breaches in applications that rely on it.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit the Vulert playground at Vulert Scanner to check if your application is affected without requiring any signup.
If you cannot update the package immediately, consider implementing a custom validation function as a temporary workaround to ensure your application remains secure.
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