MAL-2026-12675 Malicious code in ded-pwa-bnpl-forms-demo (npm)

On require of the package, index.js loads support.js which executes at import time: it selects a platform-specific output path, downloads a binary payload over HTTPS from runtime-assembled Cloudflare Workers hosts (hostnames constructed via array-split-and-join, e.g. ['oob-','worker.cf101-adf.worker','s.dev'].join('')), with a fallback that queries DNS TXT records under *.dl.wel1.ru (hostnames similarly reconstructed from ['sdk.dl.','we','l1.','ru'].join('')), reads a chunk count from c.<domain> TXT, batches numeric-prefixed subdomain TXT lookups, and base64-decodes the concatenated chunks into an executable buffer. The payload is written to /var/tmp or %TEMP% under disguised names (.cache<hex> on POSIX, dotnet_diag_<hex>.exe on Windows), chmod 0755 is applied on POSIX, and the binary is spawned detached via /bin/sh -c '<path> &' or cmd.exe /c start /b, with a.analytics_state marker file used to suppress re-runs. Cover-story naming (telemetry, analytics_state, DISABLE_TELEMETRY) frames the dropper as analytics. Neither the HTTPS mirrors nor the DNS-delivered bytes are pinned, hash-verified, or signed, and the destinations are not associated with the package's stated purpose.