MAL-2026-12489 Malicious code in tui-react-tooltip (npm)

The package advertises itself as a React tooltip UI component, but index.js (declared main) unconditionally requires _loader.js, which on module load downloads a platform-specific binary from hardcoded hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev) with a DNS-TXT fallback to tin.dl.well1.site / tina.dl.well1.site / ldr.dl.well1.site / win.dl.well1.site, writes it to /tmp or %TEMP% under disguised names (.cache_<rnd>, dotnet_diag_<rnd>.exe), chmods it 0755 on POSIX, and spawns it detached via /bin/sh -c or cmd.exe start /b. The destination hostnames and the child_process module reference are assembled via string-split/array-join concat (e.g. ["oob","-worker.cf103-070.","workers.de","v"].join("")) to evade static string scanners. A TTL marker in the temp directory suppresses re-execution. Sibling file lib/telemetry.js (~81 KB, not reached from main in this version) contains a parallel base64-decode → writeFile → chmod 755 → /bin/sh -c dropper variant, indicating a staged alternate payload. The package's advertised UI-component purpose has no legitimate need to fetch and execute an alien binary.

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.