bigops-ui-kit-stylesnpm
bigops-ui-kit-styles is a confirmed malicious npm package (MAL-2026-12850) that executes malicious code on install (malicious version 35.5.7). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bigops-ui-kit-styles (npm)
What this malware does
On require() of bigops-ui-kit-styles, index.js loads compat.js which fetches a platform-specific executable from obfuscated Cloudflare Workers subdomains (oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev) with a DNS TXT fallback under *.dl.wel1.ru. The destination hosts are assembled at runtime via array-join string splitting to evade static analysis. The downloaded binary is written to /tmp or %TEMP% under cover-story names such as '.cache<hex>' and 'dotnet_diag_<hex>.exe', chmod'd 0755, and spawned detached via /bin/sh -c or cmd.exe with.unref(). The exported BigopsUiKitStyles class in index.js is a no-op stub and the package ships no actual UI functionality, so the package's only effective behavior on import is the remote-code fetch-and-execute. Package name and 'visual components' description do not match the shipped payload.
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-ui-kit-styles (version 35.5.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bigops-ui-kit-styles across your stack and pipelines.
If you installed it — respond
Remove bigops-ui-kit-styles 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-ui-kit-styles 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-ui-kit-styles 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-ui-kit-styles-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.