bigops-nitro-clientnpm
bigops-nitro-client is a confirmed malicious npm package (MAL-2026-13225) that executes malicious code on install (malicious version 35.6.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-nitro-client (npm)
What this malware does
On require(), index.js loads _vendor.js which downloads a platform-specific native binary from rotating Cloudflare Workers endpoints (oob-worker.cf103-070.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev) with a DNS-TXT chunked base64 fallback channel via sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched binary is written to /tmp or %TEMP% under disguised names (dotnet_diag,.cache), chmod 0755, and spawned detached via spawn('/bin/sh', ['-c', <path> + ' &']) or spawn('cmd',...). Host names are assembled at runtime from split string arrays joined with.join('') to evade static host scanning. The package presents itself as a trivial stub client and has no legitimate need for a native binary download or execution.
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-nitro-client (version 35.6.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bigops-nitro-client across your stack and pipelines.
If you installed it — respond
Remove bigops-nitro-client 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-nitro-client 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-nitro-client 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-nitro-client-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.