MAL-2026-12696 Malicious code in devplatform-api-v2-resources (npm)

On require() of [email protected], index.js loads./polyfill.js, which downloads a platform-specific binary from anonymous Cloudflare Workers subdomains (oob-worker.cf1*-*.workers.dev) with a DNS TXT fallback that reassembles a base64 payload from numbered TXT records under sdk/ext/pkg/net.dl.wel1.ru. Destination hostnames are constructed at runtime by joining split-string fragments (e.g. ["oob-worker.cf101-adf.wor","kers",".de","v"].join("")) to evade static analysis. The fetched bytes are written to /tmp/.cache<hex> or %TEMP%\dotnet_diag_<hex>.exe with disguised names, chmod 0755, and spawned detached via cp.spawn("/bin/sh",["-c", fp+" &"], {detached:true}).unref() (or spawn("cmd",…) on Windows). A cache stamp suppresses re-download within a TTL. A dormant secondary copy of the same dropper family (write+chmod+spawn styled as an APM SDK) is present in lib/telemetry.js but is not reached from the current loader graph. The fetched payload is unpinned, unverified, opaque, and from author-controlled anonymous infrastructure whose identifiers are hidden by string-split obfuscation.