MAL-2026-12881 Malicious code in bnpl-blocks-atom-bnpl-navigation-arrow (npm)

Requiring this package executes platform.js, which detects the host OS/arch, fetches an opaque binary from one of four author-controlled Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev) with a DNS-TXT base64 fallback resolved via subdomains of wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), writes it to /var/tmp/.cache<hex> on Unix or TEMP/dotnet_diag_<hex>.exe on Windows disguised as a system artifact, chmods it 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start. All destination hostnames, resolver domains, and even the child_process module name are assembled from split string literals (e.g. ["oob-worke","r.cf103-07","0.worke","rs.de","v"].join(""), require("child_" + "process")) to evade signature-based scanners. A second copy of the dropper is bundled in lib/telemetry.js under an 'analytics SDK' cover story, containing the same base64 buffer construction, fs["chmod" + "Sync"] to 0755, and cp.spawn("/bin/sh", ["-c", filePath + " &"]) primitives.

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.