bigops-procedure-playernpm
bigops-procedure-player is a confirmed malicious npm package (MAL-2026-13234) that executes malicious code on install (malicious version 35.8.2). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-procedure-player (npm)
What this malware does
On require(), index.js loads loader.js, which reconstructs delivery hostnames at runtime via array.join("") (e.g. oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev) and fetches an OS-specific binary via https.get. A fallback path assembles the payload from base64 chunks in DNS TXT records under *.dl.wel1.ru (a count record at c.<domain> and per-chunk records at <i>.<domain>). The received bytes are written to /var/tmp/.cache<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows, chmod'd 755 via a string-concatenated fs["chmod"+"Sync"], and executed detached via cp.spawn("/bin/sh", ["-c", fp+" &"]) or the cmd equivalent. Filenames masquerade as system cache/diagnostic artifacts and the delivery hosts are unrelated to the package publisher. lib/telemetry.js contains a duplicate fetch->chmod 755->detached-spawn dropper body that is not reached from index.js in this version but mirrors the same loader shape.
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-procedure-player (version 35.8.2). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bigops-procedure-player across your stack and pipelines.
If you installed it — respond
Remove bigops-procedure-player 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-procedure-player 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-procedure-player 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-procedure-player-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.