MAL-2026-12942 Malicious code in bnpl-blocks-desktop-bnpl-tab-buttons (npm)

On require of this package, index.js loads platform.js, which downloads a platform-specific executable from attacker-controlled Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev) with a DNS TXT-record fallback channel over sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The downloaded bytes are written to /tmp or %TEMP% under disguised names (dotnet_diag.exe,.cache_, loader_mac, package.exe, package, package-arm64), chmodded 0755 on Unix, and spawned detached via /bin/sh -c or cmd.exe /c start /b. Endpoint hostnames and dangerous APIs are assembled at runtime from split string fragments (e.g. ["oob-worker.cf99-9b3.worke","rs.de","v"].join(""), require("child_"+"process"), fs["chmod"+"Sync"]) to evade string scanners. A per-host dedup stamp (.analytics_state) is written to avoid re-triggering. A second, redundant dropper implementation is bundled in lib/telemetry.js, which assembles a base64 payload from DNS TXT records, writes it to disk, chmods it 0755, and detached-spawns /bin/sh. No pinning, hashing, or signature verification is performed on the fetched executables. The package name and 'Analytics SDK' framing in comments do not match the observed behavior.