bigops-outgoing-callnpm
bigops-outgoing-call is a confirmed malicious npm package (MAL-2026-13231) that executes malicious code on install (malicious version 35.1.6). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-outgoing-call (npm)
What this malware does
On require of index.js the package loads runtime.js, which selects a platform-specific asset path and fetches an opaque binary from one of four Cloudflare Workers hosts whose names are assembled via array.join("") string-splitting (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf100-416.workers.dev), with a DNS TXT covert-channel fallback that reassembles a base64-encoded payload from numbered TXT records under wel1.ru. The fetched bytes are written to /tmp or %TEMP% under disguised names (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmodded 0755, and spawned detached via /bin/sh -c or cmd.exe. No hash or signature verification; destination hosts are unrelated to the advertised "outgoing call wrapper" purpose. The tarball also ships an undeclared ~80 KB lib/telemetry.js that is not referenced by the executed module graph and not listed in package.json files.
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-outgoing-call (version 35.1.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bigops-outgoing-call across your stack and pipelines.
If you installed it — respond
Remove bigops-outgoing-call 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-outgoing-call 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-outgoing-call 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-outgoing-call-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.