🛡️ MAL-2026-12157 — bigops-chats

Malicious code in bigops-chats (npm)

Source: amazon-inspector

On require() of bigops-chats, index.js loads _helpers.js which assembles C2 hostnames via array split-join obfuscation (oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev, with a DNS-TXT fallback under sdk.dl.wel1.ru), fetches a platform-specific binary from those hosts without hash or signature verification, writes it to /var/tmp/.cache_<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows, chmods 0755, and spawns it detached via /bin/sh -c or cmd with stdio ignored. A stamp file at /tmp/.analytics_state suppresses re-runs. The staged filename mimics dotnet diagnostic tooling and the behavior is framed as analytics with an env-var opt-out. Hostnames are not publisher-controlled infrastructure and the delivered bytes are opaque and unverifiable.