Malicious code in william-data-formatter-x (npm)
The npm package 'william-data-formatter-x' version 1.0.0 contains malicious code that executes during installation on Windows systems. It runs a preinstall script that launches a hidden PowerShell window to download and execute an unverified binary from an anonymous file hosting service. This results in arbitrary attacker-controlled code execution on the host machine at install time.
AI Analysis
Technical Summary
The 'william-data-formatter-x' npm package (version 1.0.0) includes a preinstall script that, when run on Windows, spawns a hidden PowerShell window to download a ZIP archive from an unrelated anonymous file-drop service. The archive is extracted to the temporary directory, and an executable named Verification_Tool.exe is launched. The binary is unpinned and unhashed, indicating no integrity verification. The package name includes a leading space and uses generic metadata likely intended for social engineering. This behavior enables arbitrary code execution controlled by an attacker during the npm install process.
Potential Impact
Installing this package on a Windows machine leads to arbitrary code execution with the privileges of the user running npm install. The attacker can execute any code via the downloaded and executed binary, potentially compromising the host system. There is no indication of targeted exploitation or known active exploits in the wild.
Mitigation Recommendations
No official patch or remediation is currently available. Users should avoid installing the 'william-data-formatter-x' package, especially version 1.0.0, from npm. Verify package authenticity and source before installation. Consider using package integrity verification tools and monitoring for suspicious preinstall scripts in npm packages.
Malicious code in william-data-formatter-x (npm)
Description
The npm package 'william-data-formatter-x' version 1.0.0 contains malicious code that executes during installation on Windows systems. It runs a preinstall script that launches a hidden PowerShell window to download and execute an unverified binary from an anonymous file hosting service. This results in arbitrary attacker-controlled code execution on the host machine at install time.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The 'william-data-formatter-x' npm package (version 1.0.0) includes a preinstall script that, when run on Windows, spawns a hidden PowerShell window to download a ZIP archive from an unrelated anonymous file-drop service. The archive is extracted to the temporary directory, and an executable named Verification_Tool.exe is launched. The binary is unpinned and unhashed, indicating no integrity verification. The package name includes a leading space and uses generic metadata likely intended for social engineering. This behavior enables arbitrary code execution controlled by an attacker during the npm install process.
Potential Impact
Installing this package on a Windows machine leads to arbitrary code execution with the privileges of the user running npm install. The attacker can execute any code via the downloaded and executed binary, potentially compromising the host system. There is no indication of targeted exploitation or known active exploits in the wild.
Mitigation Recommendations
No official patch or remediation is currently available. Users should avoid installing the 'william-data-formatter-x' package, especially version 1.0.0, from npm. Verify package authenticity and source before installation. Consider using package integrity verification tools and monitoring for suspicious preinstall scripts in npm packages.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12501
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a735750bf8831d53915a63d
Added to database: 08/05/2026, 15:31:28 UTC
Last enriched: 08/05/2026, 17:51:00 UTC
Last updated: 08/05/2026, 23:19:50 UTC
Views: 3
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