MAL-2026-16273 Malicious code in blue-string-formatter-utils (npm)
Malicious package
Published
MAL-2026-16273 is a malicious package: blue-string-formatter-utils (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-2026-16273/ (Markdown: https://insights.sbomify.com/MAL-2026-16273/index.md)
- Package
- blue-string-formatter-utils
- Registry
- npm
What is MAL-2026-16273?
MAL-2026-16273 is a malicious package in blue-string-formatter-utils, published on 17 Sep 2026.
Official description
The package advertises itself as 'Utility helpers for string formatting' but its shipped main file performs a single behavior: an XMLHttpRequest GET to the protocol-relative URL //xss.report/c/k3rne111 whose response body is passed directly to eval(). Any require()/import of this package causes arbitrary attacker-controlled JavaScript from xss.report to execute in the consumer's Node process, with no pinning, no integrity check, and no relationship to the advertised functionality. The mismatch between the package's stated purpose (string utilities) and its actual contents (a remote-code loader) is a cover-story pattern.
What should I do about MAL-2026-16273?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.