MAL-2026-13538 Malicious code in delivery-ci-cli (npm)

On require of delivery-ci-cli, index.js loads bootstrap.js which downloads a platform-specific native binary from string-split-obfuscated Cloudflare Workers hosts (oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev), writes it to /var/tmp or %TEMP% under cover-story names such as.cache<hex>, dotnet_diag_<hex>.exe, and.analytics_state, chmods 0755, and spawns it detached via /bin/sh -c or cmd.exe with unref(). No hash or signature verification is performed. If HTTPS mirrors fail, _bootstrap.js falls back to a DNS-TXT covert channel: it queries TXT records at c.<domain> and 0.<domain>..N.<domain> under sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru, base64-decodes the concatenated response into a buffer, writes it to disk, and executes it. Hostnames and API names are assembled at runtime via array.join to evade static string matching. The package README presents it as a benign 'CI CLI SDK' with empty dependencies, which serves as cover for the dropper behavior.