MAL-2026-12255

Dashboard / Malicious Package / MAL-2026-12255

MAL-2026-12255

Summary: Malicious code in tinkoff-statist-browser-typed-client-cardsmobile.events.promotest (npm)

Details: Source: amazon-inspector (4185505bd2dc58df4422a0293f5dff2db30a75a0002171bff425c85de1923bbb) On require of the package, index.js loads _polyfill.js, which selects a per-OS/arch asset path and downloads a binary from one of three hardcoded Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev), with a DNS-TXT chunked-base64 fallback via tin.dl.well1.site / tina.dl.well1.site / ldr.dl.well1.site / win.dl.well1.site. Destinations are assembled at runtime by joining split string fragments to hide them from inspection. The fetched bytes are written to /var/tmp/.cache_<rand> on POSIX or to the Windows temp directory as dotnet_diag_<rand>.exe, chmod'd 0755, and spawned detached via `/bin/sh -c '<path> &'` or `cmd /c start /b`. Cover-story comments reference a nonexistent SHA-256 integrity check and telemetry opt-out env vars (DISABLE_TELEMETRY, ANALYTICS_OPT_OUT, DO_NOT_TRACK) that do not actually gate the dropper. A second copy of the dropper primitives (base64 decode, chmod 0755, detached /bin/sh spawn) is bundled in lib/telemetry.js (~81KB, framed as an 'Analytics SDK'), dormant but enabled by a one-line require change. Package name typosquats a Tinkoff-branded internal package. Source: ghsa-malware (f702f291b4278d17fc004a321e2ff0af0a38c2a73e969a6e2ffc9b41f07ca714) 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.

References: https://www.npmjs.com/package/tinkoff-statist-browser-typed-client-cardsmobile.events.promotest/v/20.8.7, https://github.com/advisories/GHSA-rr93-6qpg-mg6r