Malicious Code Vulnerability in @polymarket-developers/clob-client Package
Summary
MAL-2026-1635: Malicious code in @polymarket-developers/clob-client (npm). Affects @polymarket-developers/clob-client versions 1.0.7 – 1.1.1. No fix is published. How to fix ↓
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Background
The @polymarket-developers/clob-client package is a JavaScript library used in the npm ecosystem, primarily for interacting with decentralized finance applications. It provides developers with tools to manage and execute trades on the Polymarket platform. However, recent findings have revealed that certain versions of this package contain malicious code, posing significant security risks to applications that depend on it.
Vulnerability Detail
The vulnerability stems from malicious code embedded in versions 1.0.7 to 1.1.1 of the @polymarket-developers/clob-client package. This code can potentially compromise the security of applications using the library, leading to unauthorized access or data manipulation. The issue was identified by ReversingLabs and is documented in their findings, which highlight the need for immediate action to mitigate risks associated with this vulnerability.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall @polymarket-developers/clob-clientIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
If immediate updating is not feasible, consider removing the package from your project until a secure version is available. You can do this by running the command: 'npm uninstall @polymarket-developers/clob-client'. Additionally, monitor your application for any suspicious activity.
Conclusion
The @polymarket-developers/clob-client package has been found to contain malicious code in several versions, posing a significant risk to applications that utilize it. Immediate action is required to update or remove the affected package to safeguard your application from potential threats.
See every vulnerability recorded for @polymarket-developers/clob-client →
FAQ
Versions 1.0.7, 1.0.8, 1.0.9, 1.1.0, and 1.1.1 are affected by the malicious code vulnerability.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check if your application is affected without needing to sign up.
Consider removing the package from your project and monitoring your application for any unusual behavior until a secure version is available.
The vulnerability was discovered by ReversingLabs, a cybersecurity firm specializing in threat intelligence.
Yes, it is recommended to update to the latest version of the package to ensure you are using a secure version.
