Malicious Code Injection in bytepack-probe-a7x3: SSRF Vulnerability Exploitation
Summary
MAL-2026-16364: Malicious code in bytepack-probe-a7x3 (npm). Affects bytepack-probe-a7x3 versions 1.0.0 – 1.0.1. No fix is published. How to fix ↓
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.
No signup required · Results in about 60 seconds
Background
The package bytepack-probe-a7x3 is an npm package that is used for various functionalities in JavaScript applications. However, it has been found to contain a dependency called 'leak-internal' that fetches code from an external URL, which poses a significant security risk. This dependency lacks version control and integrity checks, making it susceptible to malicious code execution.
Vulnerability Detail
The vulnerability arises from the package.json file of bytepack-probe-a7x3, which declares a dependency on 'leak-internal' sourced from an HTTPS tarball URL. During installation, npm fetches and installs the code from this URL, executing any lifecycle scripts it contains. This means that the code executed on the user's machine can be altered by the operator of the external server at any time, leading to potential SSRF (Server-Side Request Forgery) attacks. The absence of version pinning, integrity hashes, and signature checks further exacerbates the risk, allowing for arbitrary code execution within the installer's network.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall bytepack-probe-a7x3If 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 temporary workaround, you can remove the dependency on 'leak-internal' from your project by modifying the package.json file and avoiding the installation of bytepack-probe-a7x3 until a secure version is released. Additionally, consider using a package-lock.json file to lock down your dependencies to known safe versions.
Conclusion
The bytepack-probe-a7x3 package has a critical vulnerability due to its dependency on an external URL that can execute malicious code. It is essential to update the package or remove the dependency to safeguard your application from potential attacks. Regular monitoring using tools like Vulert can help maintain the security of your software.
See every vulnerability recorded for bytepack-probe-a7x3 →
FAQ
bytepack-probe-a7x3 is an npm package used in JavaScript applications, but it has been flagged for containing malicious code.
The vulnerability allows for the execution of arbitrary code on your machine, which can lead to data breaches or unauthorized access to your network.
You can use Vulert to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check your application without needing to sign up.
If an immediate update is not possible, consider removing the vulnerable dependency and using a workaround to mitigate the risk until a secure version is available.
Detailed information about the vulnerability can be found in the vulnerability report from Amazon Inspector and on various security advisory platforms.
