Malicious code in ensmallen (PyPI)

Part of the "Hades" wave of the Shai-Hulud supply-chain campaign. On 2026-06-08,
malicious phantom releases of ensmallen were published to PyPI using stolen
credentials. The package executes a bundled JavaScript payload (via the Bun
runtime) on import that harvests and exfiltrates credentials and attempts
self-propagation. This entry is a summary; behavior may not be fully
characterized here. See the linked references for detailed analysis and
indicators of compromise.