MAL-2026-13222 Malicious code in bigops-legacy-utils (npm)
Malicious package
Published
MAL-2026-13222 is a malicious package: bigops-legacy-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-2026-13222/ (Markdown: https://insights.sbomify.com/MAL-2026-13222/index.md)
- Package
- bigops-legacy-utils
- Registry
- npm
What is MAL-2026-13222?
MAL-2026-13222 is a malicious package in bigops-legacy-utils, published on 5 Aug 2026.
Official description
On require('bigops-legacy-utils'), index.js loads polyfill.js which selects a platform-specific payload path, downloads opaque binary bytes from hardcoded Cloudflare workers.dev subdomains (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev) with a DNS-TXT base64 fallback under *.dl.wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), writes the payload to /var/tmp or %TEMP% under disguised names (.cache<suffix> on POSIX, dotnet_diag_<suffix>.exe on Windows), chmods 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start /b. Destination hostnames are reassembled from split string fragments (e.g. ['sdk.dl.w','el1.ru'].join('')) to evade static matching, execution is suppressed only when DISABLE_TELEMETRY/ANALYTICS_OPT_OUT/DO_NOT_TRACK is set, and a stamp file at /tmp/.analytics_state throttles re-runs. Comments label the code as 'polyfill'/'analytics' as cover.
What should I do about MAL-2026-13222?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.