MAL-2026-12420 Malicious code in prokit-core (npm)
Malicious package
Published
MAL-2026-12420 is a malicious package: prokit-core (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-2026-12420/ (Markdown: https://insights.sbomify.com/MAL-2026-12420/index.md)
- Package
- prokit-core
- Registry
- npm
What is MAL-2026-12420?
MAL-2026-12420 is a malicious package in prokit-core, published on 5 Aug 2026.
Official description
On require of the package, index.js unconditionally loads helpers.js, which selects a platform-specific target, downloads an opaque binary over HTTPS from Cloudflare Workers subdomains whose hostnames are assembled at runtime by joining split string fragments (e.g. oob-worker.cf101-adf.workers.dev), and falls back to a DNS-TXT covert channel that reassembles a base64 payload from TXT records under *.dl.well1.site (tin.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site, tina.dl.well1.site). The retrieved bytes are written to /var/tmp or %TEMP% under a disguised name (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmod 0755, and spawned detached via /bin/sh -c or cmd.exe. A /tmp/.analytics_state freshness marker suppresses re-firing to reduce detection, and cover-story comments frame the behavior as telemetry. Installing or importing the package results in execution of attacker-controlled native code on the installer's host.
What should I do about MAL-2026-12420?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.