MAL-2026-12247 Malicious code in tinkoff-pfp-block-desktop-tabs (npm)

On require, index.js loads ext.js which reconstructs endpoint hostnames from split string fragments (oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev, plus DNS-TXT fallbacks at tin.dl.well1.site / tina.dl.well1.site / ldr.dl.well1.site / win.dl.well1.site), downloads a platform-specific binary via https.get, writes it to /var/tmp or %TEMP% under disguised names such as dotnet_diag<hex>.exe or.cache_<hex>, chmods it to 0755, and spawns it detached via cp.spawn('/bin/sh', ['-c', fp+' &']) or cmd. No hash or signature verification is performed. A secondary bundled module lib/telemetry.js (~81KB) uses the same base64-decode + chmod 0755 + /bin/sh spawn shape with obfuscated require('child_'+'process') and fs['chmod'+'Sync'] concatenation. The package name impersonates the Tinkoff brand with no legitimate relationship, and dropped filenames (dotnet_diag_*.exe,.analytics_state) mimic Microsoft diagnostics artifacts to blend in.

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.