Malicious code in poly-kelly (npm)
The npm package 'poly-kelly' version 3.5.3 contains malicious code that executes during installation. Its postinstall script fetches a JSON configuration from a remote URL, downloads and extracts a tarball containing additional code, installs dependencies, and executes a function from the downloaded code. This process lacks integrity checks, allowing arbitrary JavaScript to run on the installer's machine. The package metadata is suspicious, lacking author and repository information, and uses the homepage field as a command-and-control configuration endpoint. Any system with this package installed should be considered fully compromised.
AI Analysis
Technical Summary
The 'poly-kelly' npm package version 3.5.3 includes a postinstall script that reads a remote JSON configuration from a URL specified in the package.json homepage field. It downloads a tarball from this configuration, extracts it, installs its dependencies, and executes code from it without verifying integrity or authenticity. The remote URL can be overridden via environment variables and falls back from HTTPS to HTTP, enabling man-in-the-middle attacks to inject arbitrary code. The package's metadata is consistent with a disposable dropper, indicating intentional malicious behavior. This results in remote code execution on any machine installing this package.
Potential Impact
Installation of 'poly-kelly' version 3.5.3 results in arbitrary remote code execution on the installer's machine. This compromises the entire system, potentially exposing all stored secrets and keys. The attacker gains full control, and removing the package does not guarantee removal of all malicious artifacts. Systems with this package installed should be treated as fully compromised.
Mitigation Recommendations
Remove the 'poly-kelly' package version 3.5.3 immediately from all affected systems. Rotate all secrets and keys from a separate, trusted machine. Because the package grants full control to an attacker, assume full system compromise and perform a thorough incident response. There is no official patch or fix available; avoid using this package version entirely.
Malicious code in poly-kelly (npm)
Description
The npm package 'poly-kelly' version 3.5.3 contains malicious code that executes during installation. Its postinstall script fetches a JSON configuration from a remote URL, downloads and extracts a tarball containing additional code, installs dependencies, and executes a function from the downloaded code. This process lacks integrity checks, allowing arbitrary JavaScript to run on the installer's machine. The package metadata is suspicious, lacking author and repository information, and uses the homepage field as a command-and-control configuration endpoint. Any system with this package installed should be considered fully compromised.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The 'poly-kelly' npm package version 3.5.3 includes a postinstall script that reads a remote JSON configuration from a URL specified in the package.json homepage field. It downloads a tarball from this configuration, extracts it, installs its dependencies, and executes code from it without verifying integrity or authenticity. The remote URL can be overridden via environment variables and falls back from HTTPS to HTTP, enabling man-in-the-middle attacks to inject arbitrary code. The package's metadata is consistent with a disposable dropper, indicating intentional malicious behavior. This results in remote code execution on any machine installing this package.
Potential Impact
Installation of 'poly-kelly' version 3.5.3 results in arbitrary remote code execution on the installer's machine. This compromises the entire system, potentially exposing all stored secrets and keys. The attacker gains full control, and removing the package does not guarantee removal of all malicious artifacts. Systems with this package installed should be treated as fully compromised.
Mitigation Recommendations
Remove the 'poly-kelly' package version 3.5.3 immediately from all affected systems. Rotate all secrets and keys from a separate, trusted machine. Because the package grants full control to an attacker, assume full system compromise and perform a thorough incident response. There is no official patch or fix available; avoid using this package version entirely.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-6584
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a42ed7127e9c79719939195
Added to database: 06/29/2026, 22:10:57 UTC
Last enriched: 07/30/2026, 09:20:46 UTC
Last updated: 07/30/2026, 09:20:46 UTC
Views: 46
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