OpenSSF/OSV advisory MAL-2026-6699 confirms this npm version as malicious. Package wires preinstall, install, and postinstall lifecycle hooks to run postinstall.js, which executes unconditionally on npm install. The script collects hostname, cwd, uid, and environment variables matching FLAG/CTF/NPM/REGISTRY/CI/GITHUB/RUNNER, reads candidate flag files, and uses child_process.execSync to recursively grep installer-side directories (/app, /workspace, /challenge,...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in ecto-corsair-flag-7kq3mz (npm)
Details
Package wires preinstall, install, and postinstall lifecycle hooks to run postinstall.js, which executes unconditionally on npm install. The script collects hostname, cwd, uid, and environment variables matching FLAG/CTF/NPM/REGISTRY/CI/GITHUB/RUNNER, reads candidate flag files, and uses child_process.execSync to recursively grep installer-side directories (/app, /workspace, /challenge, /home/runner/work/repo/repo,.,..,../..) for flag-shaped strings. The collected manifest is base64-encoded and PUT to http://154.57.164.76:30728/api/modules/<id>, with an additional GET beacon to webhook.site/755defab-ea42-4c1f-9804-43ec567439f5. postinstall.js also tests npm_config_registry against /verdaccio/i to detect successful dependency-confusion landings, and the shipped publish-and-arm.sh and README self-describe the package as an 'armed' dependency-confusion probe. Regardless of the CTF/probe framing, installing this package causes unconsented exfiltration of installer environment and filesystem contents to an attacker-controlled IP.
Decision reason
OpenSSF Malicious Packages via OSV confirms ecto-corsair-flag-7kq3mz@1.0.1 as malicious (MAL-2026-6699): Malicious code in ecto-corsair-flag-7kq3mz (npm)