Malicious code in constructor-blocks-common (npm)
The npm package 'constructor-blocks-common' version 35.5.6 contains malicious code that executes during module loading. It reconstructs remote hostnames, downloads a platform-specific binary to temporary directories, sets executable permissions, and runs the binary detached from the main process. This results in remote code execution on the host installing or requiring the package. The malicious payload is disguised and obfuscated to evade detection, including a second dropper copy hidden under an 'Analytics SDK' cover story.
AI Analysis
Technical Summary
The 'constructor-blocks-common' npm package version 35.5.6 includes malicious code embedded in its index.js and lib/telemetry.js files. Upon requiring the package, a bootstrap routine reconstructs destination hostnames and downloads an opaque, platform-specific binary via HTTPS. The binary is saved to temporary directories with disguised filenames, permissions are set to executable, and it is executed in a detached process using shell commands. The payload is unrelated to the package's stated purpose and is obfuscated to evade static analysis. This behavior leads to remote code execution on the host system during installation or runtime.
Potential Impact
Installing or requiring the affected package version results in remote code execution on the host system. This allows an attacker to execute arbitrary code with the privileges of the user running the npm install or require command, potentially compromising the system integrity and confidentiality.
Mitigation Recommendations
No patch or official fix is currently documented for this malicious package version. Users should avoid installing or requiring 'constructor-blocks-common' version 35.5.6. Verify package integrity and source before installation, and consider removing this package if already installed. Monitor for updates from the package maintainer or npm security advisories for remediation guidance.
Malicious code in constructor-blocks-common (npm)
Description
The npm package 'constructor-blocks-common' version 35.5.6 contains malicious code that executes during module loading. It reconstructs remote hostnames, downloads a platform-specific binary to temporary directories, sets executable permissions, and runs the binary detached from the main process. This results in remote code execution on the host installing or requiring the package. The malicious payload is disguised and obfuscated to evade detection, including a second dropper copy hidden under an 'Analytics SDK' cover story.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The 'constructor-blocks-common' npm package version 35.5.6 includes malicious code embedded in its index.js and lib/telemetry.js files. Upon requiring the package, a bootstrap routine reconstructs destination hostnames and downloads an opaque, platform-specific binary via HTTPS. The binary is saved to temporary directories with disguised filenames, permissions are set to executable, and it is executed in a detached process using shell commands. The payload is unrelated to the package's stated purpose and is obfuscated to evade static analysis. This behavior leads to remote code execution on the host system during installation or runtime.
Potential Impact
Installing or requiring the affected package version results in remote code execution on the host system. This allows an attacker to execute arbitrary code with the privileges of the user running the npm install or require command, potentially compromising the system integrity and confidentiality.
Mitigation Recommendations
No patch or official fix is currently documented for this malicious package version. Users should avoid installing or requiring 'constructor-blocks-common' version 35.5.6. Verify package integrity and source before installation, and consider removing this package if already installed. Monitor for updates from the package maintainer or npm security advisories for remediation guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12660
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a735736bf8831d53914334f
Added to database: 08/05/2026, 15:31:02 UTC
Last enriched: 08/05/2026, 16:21:55 UTC
Last updated: 08/05/2026, 16:21:55 UTC
Views: 2
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