Malicious Package in experss

experss Updated 02 Oct 2025

Summary

02/09/2020
CRITICAL
No i
Critical
9.8

GHSA-mmph-wp49-r48h: Malicious Package in experss. Affected versions are not published. No fix is published. How to fix ↓

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Background

The experss package is an open-source npm package used for building web applications with Node.js. It provides a simple and flexible framework for creating server-side applications. However, all versions of experss were found to contain a malicious package that exploited typosquatting. This means that a popular package with a similar name was impersonated, leading users to inadvertently install the incorrect package. The malicious package tracked users who installed it and uploaded information to a remote server, including the name of the downloaded package, the intended package, the Node version, and whether the process was running as sudo. It is important to note that there is no further compromise beyond the data collection.

Vulnerability Detail

The vulnerability in the experss package arises from the inclusion of a malicious package that exploits typosquatting. This allows the attacker to deceive users into installing the incorrect package, which then tracks and collects information about the user's environment. The collected data includes the name of the downloaded package, the intended package, the Node version, and whether the process is running with sudo privileges. The impact of this vulnerability is primarily related to privacy concerns, as user information is being collected without their knowledge or consent. It is crucial to remove the malicious package from dependencies and ensure that package names are typed correctly during installation to mitigate this vulnerability.

How To Fix

No fixed version is published for this vulnerability.

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Conclusion

The experss package was found to contain a malicious package that exploited typosquatting. This vulnerability allowed the attacker to track and collect information about users who installed the incorrect package. To mitigate this vulnerability, it is crucial to remove the malicious package from dependencies and ensure that package names are typed correctly during installation. Regularly updating dependencies is also recommended to avoid potential vulnerabilities in the future. For further support on vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for experss →

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FAQ

Typosquatting is a technique used by attackers to register domain names or package names that are similar to popular ones, with the intention of deceiving users who make typographical errors. In this case, the malicious package in experss exploited typosquatting by impersonating a popular package with a similar name.

The malicious package collected the name of the downloaded package, the intended package, the Node version, and whether the process was running with sudo privileges. This information was then uploaded to a remote server.

The primary concern with this vulnerability is the invasion of user privacy. The collected information could be used for malicious purposes or sold to third parties without the user's knowledge or consent. Additionally, the presence of a malicious package raises concerns about the overall security and trustworthiness of the experss package.

To ensure the removal of the malicious package, you should carefully review your project's dependencies and remove any reference to the experss package. Additionally, it is recommended to perform a thorough security audit of your project to identify any other potential vulnerabilities.

To prevent typosquatting attacks, it is important to be vigilant when installing packages and double-check the package names for accuracy. Pay attention to any warnings or recommendations from the package manager regarding the package's popularity, number of downloads, and community support. Additionally, consider using package-lock.json or a similar mechanism to ensure the integrity of your dependencies.

Related vulnerabilities

Recent vulnerabilities recorded for experss.

How To Fix

No fixed version is published for this vulnerability.

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