MAL-2026-13183 Malicious code in dolyame-ui-skeleton (npm)

Package advertises itself as a visual/UI components library but ships a load-time binary dropper. index.js unconditionally requires./vendor.js, which on require() downloads a platform-specific binary from obfuscated Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev), writes it to a hidden cache path, chmods 0755, and spawns it detached via /bin/sh or cmd. Destination hostnames are reconstructed at runtime by joining string fragments (e.g. ["oob-worker.cf101-adf",".workers.dev"].join("") and ['sdk.dl.wel','1.r','u'].join("")) to evade static analysis. A fallback delivery path issues DNS TXT queries against sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru (c.<domain> for chunk count, then N.<domain> for base64-encoded chunks), reassembles the chunks, and executes the resulting binary — a covert channel that bypasses HTTPS egress filtering. Filenames such as analytics_state, dotnet_diag.exe, and.cache_ serve as cover for the dropped payload. There is no legitimate need for a UI component package to fetch and execute native binaries, obfuscate its destinations, or use DNS TXT for content delivery.