Malicious Code Detected in @posthog/event-sequence-timer-plugin: Security Alert
Summary
MAL-2025-190877: Malicious code in @posthog/event-sequence-timer-plugin (npm). Affects @posthog/event-sequence-timer-plugin versions 0.0.8. No fix is published. How to fix ↓
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Background
The @posthog/event-sequence-timer-plugin is an npm package designed to enhance event tracking capabilities within PostHog applications. It allows developers to measure and analyze user interactions effectively. However, this package has been identified to contain malicious code, posing significant security risks to applications utilizing it.
Vulnerability Detail
The vulnerability originates from the inclusion of malicious code within version 0.0.8 of the @posthog/event-sequence-timer-plugin. This code can potentially compromise the integrity of applications that depend on this package, leading to unauthorized access, data breaches, or other malicious activities. The malicious code was identified by Amazon Inspector, highlighting the importance of scrutinizing third-party packages for security threats.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall @posthog/event-sequence-timer-pluginIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
If an immediate update is not feasible, consider removing the @posthog/event-sequence-timer-plugin from your project until a secure version is released. You can uninstall the package using the following command: npm uninstall @posthog/event-sequence-timer-plugin.
Conclusion
The discovery of malicious code in the @posthog/event-sequence-timer-plugin underscores the importance of vigilance when using third-party packages. By updating to a secure version and utilizing monitoring tools like Vulert, developers can protect their applications from potential threats.
See every vulnerability recorded for @posthog/event-sequence-timer-plugin →
FAQ
The malicious code can compromise application security, potentially leading to unauthorized access and data breaches.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check your application without needing to sign up.
As a temporary measure, consider uninstalling the package to mitigate risks until a secure version is available.
Utilize tools like Vulert to monitor your package-lock.json file for real-time alerts on vulnerabilities.
Yes, you can use tools like npm-check-updates to automate the process of checking and updating outdated npm packages.
