PYSEC-2026-1075

    Dashboard / Vulnerabilities / PYSEC-2026-1075

    PYSEC-2026-1075

    Published: 7 Jul 2026Last Modified: 7 Jul 2026
    Aliases:
    MAL-2026-5326

    Summary: Malicious code in tiktoken-mcp (PyPI)

    Details: Part of the "Hades" wave of the Shai-Hulud supply-chain campaign. On 2026-06-08, malicious phantom releases of tiktoken-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.

    References: https://inspector.pypi.io/project/tiktoken-mcp/0.13.2/packages/5c/58/895febe9c7cc34d3e4d64699ec40ac0b378392db3cfda3c93b7af27da95d/tiktoken_mcp-0.13.2-py3-none-any.whl/tiktoken-setup.pth, https://www.endorlabs.com/learn/shai-hulud-hades-wave-hits-six-pypi-bioinformatics-packages, https://www.stepsecurity.io/blog/the-hades-campaign-pypi-packages

    Affected packages

    Package

    Name: tiktoken-mcp

    Purl: pkg:pypi/tiktoken-mcp

    Affected ranges

    Type: N/A

    Events:

    Introduced- None
    Fixed -None

    Affected versions

    0.13.1
    0.13.2

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    PYSEC-2026-1075 | CVE-DB