Malicious code in a.poltoradnev-package-c (npm)
Source: amazon-inspector
index.js (the package main) require()s setup.js, which schedules bootstrap() on process.nextTick, so the dropper fires on any require() of the package. bootstrap() loads lib/telemetry.js which performs an HTTPS GET of a platform-specific path (/pkg/package, /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe) against a rotating list of Cloudflare Workers subdomains (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev) with DNS-based fallbacks tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site. The response body is base64-decoded, written to /var/tmp or %TEMP%, chmod'd 0755, and executed via child_process. The child_process import, fs.chmodSync call, os.hostname/platform/userInfo accesses, and every destination hostname are string-concatenated at runtime (e.g. require('child_'+'process'), ['oob-wor','ker.cf',...].join('')) to defeat static scanners. setup.js additionally computes a SHA-256 install fingerprint from os.hostname(), os.userInfo().username, process.cwd(), process.version, and process.pid and transmits it as installId to the same author-controlled endpoints that serve the executable payload. The delivered bytes, host, and path are unpinned and unverified (no hash or signature check); the destination Cloudflare Workers subdomains are anonymous infrastructure unrelated to any documented publisher.
Source: ghsa-malware
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.
