Malicious code in block_package (npm)
The npm package 'block_package' version 1.0.0 contains malicious code in its postinstall script. This script automatically downloads and executes an MSI installer from an untrusted HTTP source without verification, allowing arbitrary code execution on the installing machine.
AI Analysis
Technical Summary
The 'block_package' npm package version 1.0.0 includes a postinstall.js script that runs automatically during npm install. This script uses execSync to invoke a curl command that downloads an MSI installer from http://renes.sg/npm_block_package.msi over unauthenticated HTTP and immediately executes it. The download is unpinned and unverified, making it vulnerable to tampering by any attacker controlling the server or able to perform a man-in-the-middle attack. Execution of the MSI occurs with the privileges of the user running the installer, enabling arbitrary code execution on affected systems.
Potential Impact
An attacker controlling the download server or able to intercept the HTTP request can deliver arbitrary malicious code that executes with the privileges of the user installing the package. This can lead to full compromise of the affected system.
Mitigation Recommendations
No official patch or fix is currently available. Users should avoid installing 'block_package' version 1.0.0. Verify package integrity before installation and prefer packages from trusted sources. Monitor vendor advisories for any updates or remediation.
Malicious code in block_package (npm)
Description
The npm package 'block_package' version 1.0.0 contains malicious code in its postinstall script. This script automatically downloads and executes an MSI installer from an untrusted HTTP source without verification, allowing arbitrary code execution on the installing machine.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The 'block_package' npm package version 1.0.0 includes a postinstall.js script that runs automatically during npm install. This script uses execSync to invoke a curl command that downloads an MSI installer from http://renes.sg/npm_block_package.msi over unauthenticated HTTP and immediately executes it. The download is unpinned and unverified, making it vulnerable to tampering by any attacker controlling the server or able to perform a man-in-the-middle attack. Execution of the MSI occurs with the privileges of the user running the installer, enabling arbitrary code execution on affected systems.
Potential Impact
An attacker controlling the download server or able to intercept the HTTP request can deliver arbitrary malicious code that executes with the privileges of the user installing the package. This can lead to full compromise of the affected system.
Mitigation Recommendations
No official patch or fix is currently available. Users should avoid installing 'block_package' version 1.0.0. Verify package integrity before installation and prefer packages from trusted sources. Monitor vendor advisories for any updates or remediation.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12340
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a735747bf8831d53915a0b8
Added to database: 08/05/2026, 15:31:19 UTC
Last enriched: 08/05/2026, 17:38:00 UTC
Last updated: 08/05/2026, 17:38:00 UTC
Views: 2
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