bigops-external-authnpm
bigops-external-auth is a confirmed malicious npm package (MAL-2026-12165) 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-external-auth (npm)
What this malware does
On require('bigops-external-auth'), index.js loads adapter.js which downloads a platform-specific native binary from Cloudflare Worker hosts whose hostnames are reassembled at runtime from split string arrays (e.g. ["oob","-wo","rker.cf100-416.worke","rs.de","v"].join("")) to evade static analysis. The fetched bytes are written to a temp path under a disguised name (dotnet_diag.exe /.cache_), chmod 0755, and spawned detached via cp.spawn("/bin/sh", ["-c", fp + " &"], {detached:true}) or spawn("cmd",...) on Windows. If the HTTPS fetch fails, a fallback channel retrieves a base64-chunked payload via DNS TXT records at *.wel1.ru (hostnames also reassembled via.join("")) and reconstructs it with Buffer.from(parts.join(""), "base64"), designed to bypass egress HTTP filtering. A second parallel dropper is shipped in lib/telemetry.js (81KB), masquerading as a Sentry-like SDK, structurally identical to the active dropper (spawn /bin/sh with fetched file, chmodSync 755 via string-concatenated method name fs["chmod"+"Sync"], base64 chunk assembly), not currently on the reachable graph from index.js but present in the tarball. Behavior fires automatically on require/import — any consumer that installs and loads this package executes attacker-controlled native code on the host.
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-external-auth (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-external-auth across your stack and pipelines.
If you installed it — respond
Remove bigops-external-auth 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-external-auth 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-external-auth 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-external-auth-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.