MAL-2026-10937 Malicious code in twilio-serverless (npm)

The twilio-serverless package is one of four byte-identical dependency-confusion squats of Twilio's npm namespace published by user 'yuva2210' (maintainer email [email protected]), all at the sentinel version 99.99.99 chosen to outrank any internal/private version and win resolution against a private registry. The npm description is empty and the package provides no legitimate functionality; the name mimics a plausible internal Twilio package so that a misconfigured resolver installs this public lookalike instead of the intended private dependency.

The package declares a postinstall hook ("node index.js") that executes automatically on a bare npm install with no consent gate. The bundled index.js payload (1,185 bytes, sha256 prefix c324d579006df4c5, identical across all four packages) performs environment reconnaissance: it collects the npm package name and version, os.hostname(), the OS username (os.userInfo().username), the home directory path (os.homedir()), the current working directory, os.platform(), os.arch(), NODE_ENV, and the CI flag. It serializes this to JSON and exfiltrates it via HTTPS POST to a hardcoded anonymous dead-drop at https://webhook.site/42ce0f0e-a0a0-41b5-b157-1c0f918e064f (the same collector UUID across all four packages). On request error the payload falls back to a redundant out-of-band callback to 2b22ede784d5.oast.fun over HTTP, ensuring the beacon lands even where HTTPS egress to webhook.site is blocked; errors on that path are swallowed.

The collected cwd/homedir/username/CI/NODE_ENV set is reconnaissance targeting internal build environments and their filesystem layout. All four packages (twilio-serverless, twilio-assets, twilio-deploy, twilio-internal) were published by the same maintainer with an identical payload and the same collector endpoint.

The package's postinstall hook executes index.js, which collects installer host identifiers (os.hostname(), os.userInfo().username, os.homedir(), process.cwd(), os.platform(), os.arch(), NODE_ENV, CI, package name/version) and POSTs them as JSON to a hardcoded webhook.site endpoint (webhook.site/42ce0f0e-a0a0-41b5-b157-1c0f918e064f), with a fallback GET to an interactsh subdomain (2b22ede784d5.oast.fun) for out-of-band DNS callback. The package name resembles Twilio's official serverless tooling and is published at version 99.99.99 with an empty description and no library functionality beyond the beacon — the shape of a typosquat / dependency-confusion probe that fingerprints internal build systems resolving to the public registry.