The twilio-serverless package is one of four byte-identical dependency-confusion squats of Twilio's npm namespace published by user 'yuva2210' (maintainer email charankumarj2004@gmail.com), 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.
{
"malicious-packages-origins": null
}[
{
"name": "Embedded Malicious Code",
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature."
}
]
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/twilio-serverless/MAL-2026-10937.json"
{
"domains": [
"webhook.site",
"2b22ede784d5.oast.fun"
],
"urls": [
"https://webhook.site/42ce0f0e-a0a0-41b5-b157-1c0f918e064f"
]
}