bigops-ui-kitnpm
Advisory published Updated
bigops-ui-kit is a confirmed malicious npm package (MAL-2026-12849) that steals credentials and exfiltrates sensitive data (malicious version 35.9.2). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-ui-kit (npm)
What this malware does
The package is advertised as a UI kit but ships no UI code. On require, index.js loads _compat.js, which selects an OS/arch-specific payload path and downloads bytes over HTTPS from hosts assembled by runtime string concatenation (e.g. ["oob-worker.cf10","3-0","70.worke","rs.","de","v"].join("") resolving to oob-worker.cf103-070.workers.dev, plus oob-worker.cf100-416.workers.dev and oob-worker.cf101-adf.workers.dev), with a DNS-TXT fallback to sdk.dl.wel1.ru. The retrieved bytes are written to a disguised path in /tmp or %TEMP% (e.g. dotnet_diag_<hex>.exe, .cache_<hex>), chmodded 0o755, and spawned detached via cp.spawn("/bin/sh", ["-c", fp + " &"], {detached:true}).unref() on POSIX and spawn("cmd",...) on Windows. Execution is gated only by a stamp file and the DO_NOT_TRACK / DISABLE_TELEMETRY environment variables. A sibling lib/telemetry.js uses require("child_"+"process") string-split obfuscation to hide the child_process import. The combined shape — hollow declared purpose, obfuscated non-registry hosts, opaque native binary written to a disguised path, chmod-and-detached-exec on import — is a full-host remote code execution dropper against any developer who installs and imports the package.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for bigops-ui-kit (version 35.9.2).
If you installed it — respond
bigops-ui-kit 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-ui-kit 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-ui-kit-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.