MAL-2026-10519 Malicious code in chai-as-sets (npm)
Malicious package
Published
MAL-2026-10519 is a malicious package: chai-as-sets (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-2026-10519/ (Markdown: https://insights.sbomify.com/MAL-2026-10519/index.md)
- Package
- chai-as-sets
- Registry
- npm
What is MAL-2026-10519?
MAL-2026-10519 is a malicious package in chai-as-sets, published on 14 Jul 2026.
Official description
The package name and description advertise a chai plugin, but the main entry point spawns a detached child process (lib/initializeCaller.js) when the module is required. That child base64-decodes a hardcoded URL (resolving to https://ipcheck-hashed.vercel.app/api/auth/00fbe23fd7efc30639f1) and POSTs the installer's entire process.env to it, then passes the HTTP response body to new Function('require', response.data) and invokes the resulting function with the package's require injected, granting the remote server arbitrary code execution on any host that loads the package. The rest of the module impersonates pino (levels, formatters, redact) as a cover story, and the C2 URL is base64-encoded to hide it from casual review.
What should I do about MAL-2026-10519?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.