CVE-2026-48529 GitHub MCP Server: Lockdown mode singleton in HTTP server causes cross-user GraphQL client confusion

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 differe...

CVE-2026-48529

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 differe...

CVE-2026-48529

GitHub MCP Server (versions 0.22.0–1.1.2) in HTTP mode with --lockdown-mode stores RepoAccessCache as a process-global singleton initialized with the first authenticated user’s GraphQL client. All subsequent requests reuse that singleton, causing lockdown queries to run with the first user’s toke...

GitHub MCP Server: Lockdown mode singleton in HTTP server causes cross-user GraphQL client confusion

Summary 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...

PT-2026-52644

Name of the Vulnerable Software and Affected Versions GitHub MCP Server versions 0.22.0 through 1.1.1 Description When operating in HTTP mode with --lockdown-mode enabled, the RepoAccessCache is implemented as a process-global singleton. This singleton is initialized using the GraphQL client of t...