CVE-2026-47427

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/github/github-mcp-server/commit/c88d2ecdd3bb07f7bdd75296e3ee676febf14f58	Patch
https://github.com/github/github-mcp-server/pull/2502	Issue Tracking Patch
https://github.com/github/github-mcp-server/releases/tag/v1.1.0	Release Notes
https://github.com/github/github-mcp-server/security/advisories/GHSA-w4q6-qw23-4rg7	Exploit Vendor Advisory
https://github.com/github/github-mcp-server/security/advisories/GHSA-w4q6-qw23-4rg7	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:github:mcp_server:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-28 16:18

Updated : 2026-08-08 01:24

NVD link : CVE-2026-47427

Mitre link : CVE-2026-47427

CVE.ORG link : CVE-2026-47427

JSON object : View

Products Affected

github

mcp_server

CWE

CWE-476

NULL Pointer Dereference

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