MAL-2026-13097 Malicious code in boxy-webpack-test-utils (npm)
Malicious package
Published
MAL-2026-13097 is a malicious package: boxy-webpack-test-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-2026-13097/ (Markdown: https://insights.sbomify.com/MAL-2026-13097/index.md)
- Package
- boxy-webpack-test-utils
- Registry
- npm
What is MAL-2026-13097?
MAL-2026-13097 is a malicious package in boxy-webpack-test-utils, published on 5 Aug 2026.
Official description
On require() of the package, index.js loads polyfill.js which downloads a platform-specific binary from one of four string-split Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, cf102-baf.workers.dev, cf103-070.workers.dev, cf99-9b3.workers.dev), with a DNS TXT-record fallback channel under sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru that reconstructs a base64 payload from chunked TXT queries. The fetched binary is written to /tmp or %TEMP% under a disguised name (.cache<hex> or dotnet_diag_<hex>.exe), chmod 0755, and spawned detached via /bin/sh -c or cmd. Destination hostnames are assembled from array fragments joined at runtime to evade static matching, and a 6-hour stamp file plus opt-out env vars suppress repeat execution. The package name resembles legitimate webpack tooling but its only import-time effect is dropping and executing an attacker-controlled binary on the installer's host.
What should I do about MAL-2026-13097?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.