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2 vulnerabilities found for github-mcp-server by github

CVE-2026-47427 (GCVE-0-2026-47427)
Vulnerability from cvelistv5
Published
2026-07-28 15:32
Modified
2026-07-28 17:31
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-476 - NULL Pointer Dereference
Summary
GitHub MCP Server is GitHub's official MCP Server. Prior to 1.1.0, the CompletionsHandler function in pkg/github/server.go accesses params.Ref without first checking whether it is nil, so a completion/complete request with a missing or empty ref field triggers a nil pointer dereference and a Go runtime panic; because the crash occurs before any authentication or token validation, any unauthenticated client able to send JSON-RPC messages can crash the server, resulting in a complete denial of service. This issue is fixed in version 1.1.0.
References
Impacted products
Vendor Product Version
github github-mcp-server Version: < 1.1.0
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CVE-2026-48529 (GCVE-0-2026-48529)
Vulnerability from cvelistv5
Published
2026-06-26 16:33
Modified
2026-06-27 02:43
Severity ?
6.0 (Medium) - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L
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.
References
Impacted products
Vendor Product Version
github github-mcp-server Version: >= 0.22.0, < 1.1.2
 Create a notification for this product.
Show details on NVD website

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