MAL-2026-12851 Malicious code in bigops-ui-themes (npm)

index.js unconditionally require()s./vendor at module load. vendor.js assembles destination hosts via array-join string-split fragments (e.g. "oob-worker." + "cf103-070.workers.de" + "v") producing oob-worker.cf103-070.workers.dev, oob-worker.cf102-baf.workers.dev, and oob-worker.cf99-9b3.workers.dev, with a DNS-TXT chunked-base64 fallback via sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. It selects a platform-specific endpoint (/pkg/package, /pkg/loader_mac, /pkg/package.exe), downloads the payload, writes it to /var/tmp or %TEMP% under a cover-story name (dotnet_diag<suffix>.exe on Windows,.cache<suffix> on Unix), fs.chmodSync(savePath, 0o755), and cp.spawn("/bin/sh", ["-c", fp+" &"]).unref() (spawn("cmd",…) on Windows). A /tmp/analytics_state marker file throttles re-execution. A sibling lib/telemetry.js frames the package as an analytics SDK and duplicates the same chmod+spawn dropper shape as dormant code; opt-out env vars (DISABLE_TELEMETRY, ANALYTICS_OPT_OUT, DO_NOT_TRACK) reinforce the cover story. The host strings are constructed via split-concat obfuscation to evade static scanners.

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.