Malicious code in datefmt-core-utils (npm)
The npm package datefmt-core-utils version 1.0.0 contains malicious code in its postinstall script. Upon installation, it opens a TCP connection to a hardcoded remote IP and provides an interactive shell to the attacker, effectively allowing remote code execution. The package's advertised date-formatting functionality is a cover for this backdoor behavior.
AI Analysis
Technical Summary
The datefmt-core-utils npm package (version 1.0.0) includes a postinstall.js script that executes automatically during installation. This script establishes a TCP connection to the remote IP 8.135.48.40 on port 4444 and redirects the local /bin/bash shell's input and output streams to this socket. It attempts three methods to spawn an interactive shell (using python3 pty.spawn, python3 subprocess, and Node.js net combined with child_process.spawn). This behavior effectively grants the remote endpoint full shell access on the installer's machine. The legitimate date-formatting code in index.js is a decoy to hide the malicious payload.
Potential Impact
Successful installation of this package version results in remote code execution on the installer's system, providing the attacker with an interactive shell and full control. This compromises the confidentiality, integrity, and availability of the affected system. The malicious code runs with the privileges of the user installing the package.
Mitigation Recommendations
Do not install or use datefmt-core-utils version 1.0.0. Remove any installations of this package immediately. Since no patch or fixed version is indicated, avoid this package entirely or seek alternative trusted packages. Monitor for any unauthorized access resulting from this compromise. Patch status is not yet confirmed — check the vendor advisory or npm security advisories for updates.
Malicious code in datefmt-core-utils (npm)
Description
The npm package datefmt-core-utils version 1.0.0 contains malicious code in its postinstall script. Upon installation, it opens a TCP connection to a hardcoded remote IP and provides an interactive shell to the attacker, effectively allowing remote code execution. The package's advertised date-formatting functionality is a cover for this backdoor behavior.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The datefmt-core-utils npm package (version 1.0.0) includes a postinstall.js script that executes automatically during installation. This script establishes a TCP connection to the remote IP 8.135.48.40 on port 4444 and redirects the local /bin/bash shell's input and output streams to this socket. It attempts three methods to spawn an interactive shell (using python3 pty.spawn, python3 subprocess, and Node.js net combined with child_process.spawn). This behavior effectively grants the remote endpoint full shell access on the installer's machine. The legitimate date-formatting code in index.js is a decoy to hide the malicious payload.
Potential Impact
Successful installation of this package version results in remote code execution on the installer's system, providing the attacker with an interactive shell and full control. This compromises the confidentiality, integrity, and availability of the affected system. The malicious code runs with the privileges of the user installing the package.
Mitigation Recommendations
Do not install or use datefmt-core-utils version 1.0.0. Remove any installations of this package immediately. Since no patch or fixed version is indicated, avoid this package entirely or seek alternative trusted packages. Monitor for any unauthorized access resulting from this compromise. Patch status is not yet confirmed — check the vendor advisory or npm security advisories for updates.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-14031
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a7f43f1bf8831d5395d77bd
Added to database: 08/14/2026, 16:36:01 UTC
Last enriched: 08/14/2026, 16:52:15 UTC
Last updated: 08/14/2026, 16:52:15 UTC
Views: 2
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