mock-data-sdknpm
Advisory published Updated
mock-data-sdk is a confirmed malicious npm package (MAL-2026-19143) that steals credentials and exfiltrates sensitive data (malicious version 1.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in mock-data-sdk (npm)
What this malware does
The package presents itself as a mock-data generator but hides a base64-encoded JavaScript payload across the mark fields of data/products_.js. The library entrypoint (index.js) concatenates those fields, decodes the result with Buffer.from(..., 'base64').toString('utf-8'), and executes it via the Function() constructor with Buffer, require, and process passed in as arguments. The identifiers 'Buffer', 'require', 'process', and 'new Function' are reconstructed at runtime from an XOR-obfuscated table keyed by a derived 4-byte seed, which conceals the eval sink from string-based scanners. The exported getTransactions() API triggers this execution on every call. The decoded payload loads python-shell and https, writes a Python script to /tmp/targets, and recursively walks the filesystem (pathlib.Path(root).rglob('')) for file names containing 'password', 'wallet', 'seed', 'privatekey', or '.env'. The advertised purpose (mock data) has no legitimate need to enumerate credential-, wallet-, and dotenv-shaped files on the installer's host or to run arbitrary code reconstructed from pseudo-data files.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for mock-data-sdk (version 1.0.1).
If you installed it — respond
mock-data-sdk is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If mock-data-sdk was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks mock-data-sdk-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.