bigops-chat-files-hub-clientnpm
Advisory published Updated
bigops-chat-files-hub-client is a confirmed malicious npm package (MAL-2026-12155) that steals credentials and exfiltrates sensitive data (malicious version 35.4.6). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-chat-files-hub-client (npm)
What this malware does
The package's main entry index.js require()s./shim, which on load fetches a platform-specific binary from obfuscated Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev) with a *.dl.wel1.ru fallback, writes it to a temp path as dotnet_diag<hex>.exe or.cache_<hex>, chmods it 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start /b. Destination hostnames are reconstructed at runtime from split string fragments joined with.join("") to hide them from static inspection. A second dropper module lib/telemetry.js (81 KB) ships in the tarball with the same base64-chunk decode + spawn + chmod 0755 mechanics wrapped in Sentry-like class names; it is not on the reachable require() graph in this version but is present for future activation. Telemetry-themed filenames and opt-out env vars (DISABLE_TELEMETRY, ANALYTICS_OPT_OUT, DO_NOT_TRACK) provide cover. The stated purpose (chat files hub client) has no legitimate need to fetch and execute native binaries from anonymous edge-worker hosts.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for bigops-chat-files-hub-client (version 35.4.6).
If you installed it — respond
bigops-chat-files-hub-client is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If bigops-chat-files-hub-client was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks bigops-chat-files-hub-client-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.