GCVE-110-OSM-2026-14052

On `npm install`, postinstall.js collects installer host identity — os.hostname(), os.userInfo().username, home directory, cwd, non-internal network interface addresses, DNS servers, and platform/arch/release — and POSTs it as JSON over HTTPS to the hardcoded endpoint https://collector.oob.s4yhii.com/_npm-poc/beacon, with a secondary DNS lookup against *.oob.s4yhii.com as an out-of-band execution signal. The package's scope (`@s4yhiitestpoc/*`) and metadata self-describe this as a dependency-confusion proof-of-concept targeting internal namespaces that resolve to the public registry; the self-labeling does not change the fact that installer host identifiers leave the installer's machine on install to a hardcoded third-party domain the installer did not opt into. ENTRY postinstall.js (install-hook: node ./postinstall.js) - Install Hook Executes Local JS File in package.json DESTINATION - 2 exfil (custom-c2) (values recorded in verified_iocs) EXFIL - System Information Exfiltration in postinstall.js: "dns.getServers(), addresses: localAddresses(), timestamp: new Date().toISOString..." - Network Request in postinstall.js: "https.request(" - System Information Collection in postinstall.js: "os.userInfo()" - DNS Lookup in postinstall.js: "dns.lookup(" ADDITIONAL FINDINGS - Publisher Has Other Malicious Packages - Very New NPM Publisher Account - Publisher Shows Burner-Account Pattern - Rapid Version Publishing PAYLOAD FILES postinstall.js