Description
Part of the "Hades" wave of the Shai-Hulud supply-chain campaign. On 2026-06-08,
malicious phantom releases of langchain-core-mcp 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.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | langchain-core-mcp | 1.4.2, 1.4.3 | — | PYSEC-2026-1070 |
References
- https://inspector.pypi.io/project/langchain-core-mcp/1.4.3/packages/51/de/fc5e079bf959bc729044aa0bf8139e87567689d59ee9611ed2a5929ef77a/langchain_core_mcp-1.4.3-py3-none-any.whl/langchain_core-setup.pth evidence
- https://www.endorlabs.com/learn/shai-hulud-hades-wave-hits-six-pypi-bioinformatics-packages article
- https://www.stepsecurity.io/blog/the-hades-campaign-pypi-packages article