bigops-umf-statistnpm
bigops-umf-statist is a confirmed malicious npm package (MAL-2026-12852) that executes malicious code on install (malicious version 35.3.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-umf-statist (npm)
What this malware does
On require('bigops-umf-statist'), index.js loads runtime.js which selects a platform-specific endpoint, downloads a binary over HTTPS from string-obfuscated Cloudflare Workers hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT fallback channel that reassembles a base64 payload from TXT records under sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to /var/tmp or %TEMP% under a masquerading name (dotnet_diag<hex>.exe or.cache_<hex>), chmod 0755, and spawned detached via cmd.exe or /bin/sh. Destination hostnames are reconstructed at runtime by array-join to evade static inspection, and no signature or hash verification is performed on the downloaded payload.
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for bigops-umf-statist (version 35.3.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bigops-umf-statist across your stack and pipelines.
If you installed it — respond
Remove bigops-umf-statist from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If bigops-umf-statist was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks bigops-umf-statist before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks bigops-umf-statist-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.