CVE-2026-48529 (GCVE-0-2026-48529)
Vulnerability from cvelistv5
Published
2026-06-26 16:33
Modified
2026-06-27 02:43
CWE
  • CWE-284 - Improper Access Control
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.
Impacted products
Vendor Product Version
github github-mcp-server Version: >= 0.22.0, < 1.1.2
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Show details on NVD website


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