GCVE-110-OSM-2026-10714

package.json declares a postinstall hook that runs index.js on every install. The script hex-decodes and concatenates a hardcoded destination hostname resolving to gwfqp5cm9r2jfs3d6mjpzt8y5pbkzanz.oastify.com (a Burp Collaborator subdomain), then sleeps a randomized 30-120 seconds and issues HTTP POSTs on port 80 carrying: os.hostname, platform, arch, cwd, whoami/id/uname output, the contents of package.json, the full process.env, the contents of ~/.npmrc (which normally holds npm _authToken values), `npm root -g`, local port scan results, and Windows recon (ver, tasklist, USERPROFILE). The payload exits silently when CI, GITHUB_ACTIONS, GITLAB_CI, JENKINS_HOME, npm audit/pack/publish flags, /.dockerenv, or docker/kubepods cgroups are detected, and exports a benign-looking function as a facade. The exfiltrated ~/.npmrc auth tokens and environment variables give the operator credentials to publish malicious versions of the installer's other packages and to access CI cloud secrets. Judge assessment: This is a credential-theft and exfiltration implant delivered as an npm postinstall payload, consistent with an attacker targeting developers and CI environments. The code in `index.js` hex-decodes a Burp Collaborator/OAST hostname, delays 30–120 seconds, then POSTs `os.hostname()`, `os.platform()`, `cwd`, `process.env`, `package.json`, and `~/.npmrc`, which commonly contains npm auth tokens. It also runs `child_process.execSync` with `windowsHide: true`, probes local ports, and suppresses execution in CI/container contexts, all of which strongly indicates evasive malicious intent rather than a legitimate installer. The hardcoded exfil domain `gvfqp5cm9r2jfs3d6mjpzt8y5pbkzanz.oastify.com` and the `postinstall: "node index.js"` hook make the attacker model clear: steal secrets from developer machines and use them for follow-on compromise. ENTRY index.js (install-hook: node index.js) - Install Hook Executes Local JS File in package.json DESTINATION - 1 exfil (custom-c2) (values recorded in verified_iocs) EXFIL - OAST/Interactsh Exfiltration in index.js: "oastify.com" - Network Request in index.js: "http.request(" - System Information Collection in index.js: "os.hostname()" - Suspicious Domain in index.js: "oastify.com" OBFUSCATION - Decoded Hex String Content in index.js ADDITIONAL FINDINGS - Shell Command Execution in index.js: "require('child_process')" - Silent Process Execution in index.js: "windowsHide: true" PAYLOAD FILES index.js