OpenSSF/OSV advisory MAL-2026-12249 confirms this npm version as malicious. On require() of the package, _helpers.js selects a platform-specific binary path, downloads bytes from one of four hardcoded Cloudflare Workers hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev) with DNS-based fallback via subdomains of well1.site (tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site),...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in tinkoff-pfp-block-mobile-panels (npm)
Details
On require() of the package, _helpers.js selects a platform-specific binary path, downloads bytes from one of four hardcoded Cloudflare Workers hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev) with DNS-based fallback via subdomains of well1.site (tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site), writes the payload to /tmp or %TEMP% under a disguised name (.cache_<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmods 0755, and spawns it detached via /bin/sh -c or cmd.exe. Host names and dangerous API names (child_process, chmodSync) are assembled at runtime from split strings via.join('') to evade static analysis. index.js unconditionally require('./_helpers'), so the dropper fires on any import of the package. A second dropper variant with the same shape ships in lib/telemetry.js (~81KB, currently unreferenced from index.js). Package name impersonates the Tinkoff brand and README references an 'internal tracker' to suggest insider legitimacy, consistent with a dependency-confusion lure targeting Tinkoff-adjacent developer workstations.
Decision reason
OpenSSF Malicious Packages via OSV confirms tinkoff-pfp-block-mobile-panels@20.2.7 as malicious (MAL-2026-12249): Malicious code in tinkoff-pfp-block-mobile-panels (npm)