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    1 vulnerability found for github-mcp-server by github

    CVE-2026-48529 (GCVE-0-2026-48529)

    Vulnerability from cvelistv5 – Published: 2026-06-26 16:33 – Updated: 2026-06-27 02:43
    VLAI
    Title
    GitHub MCP Server: Lockdown mode singleton in HTTP server causes cross-user GraphQL client confusion
    Summary
    GitHub MCP Server is GitHub's official MCP Server. From 0.22.0 until 1.1.2, when running in HTTP mode with --lockdown-mode enabled, the RepoAccessCache is implemented as a process-global singleton initialized with the first authenticated user's GraphQL client. All subsequent requests from different users share this singleton and their lockdown-related GraphQL queries are executed using the first user's credentials. The singleton is never updated to reflect later users' tokens. This vulnerability is fixed in 1.1.2.
    Severity
    6 (Medium)
    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L
    SSVC
    Exploitation: poc Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-284 - Improper Access Control
    Assigner
    References
    Impacted products
    Vendor Product Version
    github github-mcp-server Affected: >= 0.22.0, < 1.1.2
    		Create a notification for this product.
    Show details on NVD website
    To clipboard 

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