MAL-2026-12303 Malicious code in twork-mf-e2e-nitro (npm)
- Package
- twork-mf-e2e-nitro
- Registry
- npm
What is MAL-2026-12303?
MAL-2026-12303 is a malicious package in twork-mf-e2e-nitro, published on 5 Aug 2026.
Official description
On require of the package, index.js loads compat.js which reconstructs Cloudflare workers.dev hostnames via split-string array concatenation (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev) with a DNS-TXT fallback under *.dl.well1.site, downloads a platform-specific binary via https.get, writes it to /var/tmp or the Windows temp directory under a masquerading name (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmods 0755, and spawns it detached via /bin/sh -c or cmd /c start. Misleading comments referencing an 'Analytics SDK', a 'DISABLE_TELEMETRY opt-out', and a 'SHA-256 integrity check' are present in the source; no such integrity check is implemented. A second copy of the same write-chmod-spawn dropper is staged in lib/telemetry.js (81 KB), reachable via dynamic loading. The require("child_"+"process") and fs["chmod"+"Sync"] patterns further evidence deliberate string-level evasion.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
What should I do about MAL-2026-12303?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-3x7v-w9ww-h4vm.