MAL-2026-12989 Malicious code in bnpl-blocks-mobile-bnpl-floating-button (npm)

On require(), index.js loads support.js whose top-level main() downloads a platform-specific binary from author-controlled hosts assembled via string-array concatenation (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev, sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru) with a DNS-TXT base64 fallback. The fetched bytes are written to /tmp or %TEMP% under stealth names such as dotnet_diag<hex>.exe and.cache_<hex>, chmod'd 0755 on POSIX (with the API name assembled as 'chmod'+'Sync'), and executed detached via /bin/sh -c '<path> &' or cmd /c start /b. A second dropper is shipped in lib/telemetry.js (81KB, framed as an 'Analytics SDK') implementing the same base64-decode + chmod-via-string-concat + detached spawn pattern as an alternate loader. child_process is resolved via require('child_' + 'process') and destination hostnames are split across arrays to evade static analysis. No version pin, no hash or signature verification, and a /tmp stamp file is used for rate-limiting. The package name and metadata claim a mobile BNPL floating-button UI component, which conflicts with the shipped behavior.

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.