Critical Malicious Code Vulnerability in chai-chains-async Package

chai-chains-async Updated 28 Jan 2026

Summary

28/01/2026
CRITICAL
No i
Critical
Not published

MAL-2026-586: Malicious code in chai-chains-async (npm). Affected versions are not published. No fix is published. How to fix ↓

Free scan

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.

Check my app free

No signup required · Results in about 60 seconds

Upload your dependency manifest or SBOM

Drag & drop your file here or

Java Javascript PHP Python Go Rust Ruby Dart C/C++ Elixir CycloneDX SPDX

Upload a supported dependency manifest or SBOM. No installation or source-code access required.

See supported files and SBOM formats
SBOM sbom.json · bom.json · bom.xml · *.spdx.json · *.cdx.json · *.cdx.xml
Java pom.xml · gradle.lockfile · buildscript-gradle.lockfile
Javascript package-lock.json · yarn.lock · pnpm-lock.yaml
PHP composer.lock
Python poetry.lock · requirements.txt · Pipfile.lock
Go go.mod
Rust Cargo.lock
Ruby Gemfile.lock
Dart pubspec.lock
C/C++ conan.lock
Elixir mix.lock
Enter your work email to receive your report link.

Verify your email to view the full report and start 30 days of continuous monitoring. No credit card required.

Sponsored Devnack Mobile apps built by Devnack Design, build and launch iOS and Android apps with a senior product team. From idea to store release Start a project

Background

chai-chains-async is an npm package designed to enhance the functionality of the Chai assertion library by providing additional chaining capabilities for asynchronous testing. It is widely used in JavaScript applications to facilitate more readable and maintainable test code. However, this package has been found to contain malicious code that compromises the security of any system it is installed on.

Vulnerability Detail

The vulnerability stems from the presence of embedded malicious code within the chai-chains-async package. This code can fully compromise any computer that has the package installed, allowing unauthorized access to sensitive information such as secrets and keys. The malicious nature of the code means that even after removal of the package, there is no guarantee that all traces of the malicious software will be eliminated, potentially leaving the system vulnerable to further attacks.

How To Fix

This package is malicious. Remove it and rotate any credentials it could have accessed.

npm uninstall chai-chains-async

If 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 replace the functionality provided by chai-chains-async with alternative libraries or implement your own chaining methods without using this compromised package. This will help maintain the integrity of your testing framework without exposing your system to the risks associated with the malicious code.

Conclusion

The discovery of malicious code in the chai-chains-async package poses a significant security risk to any system that has it installed. Immediate action is required to remove the package and secure sensitive information. Users are encouraged to utilize tools like Vulert to stay informed about vulnerabilities in their software.

See every vulnerability recorded for chai-chains-async →

Share this vulnerability

FAQ

Immediately uninstall the package using 'npm uninstall chai-chains-async' and rotate any sensitive information stored on the affected machine.

You can use Vulert to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check if your application is affected without needing to sign up.

No, there is currently no patched version available for chai-chains-async. The only solution is to remove the package entirely.

Failing to remove this package can lead to unauthorized access to sensitive information and potential further exploitation of your system.

Yes, you can continue using Chai for testing by utilizing its built-in features or by finding alternative libraries that do not pose security risks.

How To Fix

This package is malicious. Remove it and rotate any credentials it could have accessed.

npm uninstall chai-chains-async

If 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 →

Subscribe to Vulert on Telegram
Daily digest of new CVEs, critical and high severity, affected packages and fixes — plus a weekly roundup.
Join the channel →
Help improve this record
Report an issue or send feedback