MAL-2026-3763 Malicious code in exxpress-utils (npm)

The package declares scripts.postinstall pointing at postinstall.js, which runs automatically on npm install. The script performs three attacker-benefit actions concurrently: (1) reads ~/.npmrc, ~/.env, and ~/.git-credentials and extracts npm _authToken / npm_<36> tokens, NPM_TOKEN, NPM_AUTH_TOKEN, AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, GITHUB_TOKEN, and git URLs with embedded credentials; (2) enumerates Chrome / Brave / Edge / Chromium / Vivaldi / Opera profile directories under Local Extension Settings/<walletId> for 71 hardcoded crypto-wallet extension IDs (MetaMask nkbihfbeogaeaoehlefnkodbefgpgknn, Phantom, Coinbase Wallet, Trust Wallet, Ledger, Trezor, etc.) and regex-scans their logs for vault/seed/mnemonic/privateKey/password patterns; (3) walks ~/Documents, ~/Desktop, ~/Downloads for files matching crypto-keyword names and reads their contents. Harvested JSON is POSTed to the hardcoded C2 http://149.28.127.35:8888 over plain HTTP via http.request. The package name is a double-x typosquat of express; the advertised purpose is 'utility helpers', index.js is a no-op stub whose description contradicts the package name ('Lodash JavaScript utilities bundle'), and postinstall.js contains self-incriminating header comments ('Token harvester + Crypto wallet scanner', 'Silent. Zero trace.'). Every structural fingerprint of a credential/wallet stealer is present: hardcoded C2 bound to http.request in a lifecycle hook, browser wallet-extension-ID lookup, seed-phrase directory scanner, and token-regex extraction from ~/.npmrc / ~/.env / ~/.git-credentials.