CVE Catalog

CVE-2026-47427

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.41%

34th percentile - higher than 34% of all known CVEs

Summary

A vulnerability in GitHub MCP Server causes a Go panic (nil pointer dereference) when handling a completion/complete request with a missing or empty ref field. Since the crash occurs before authentication, any unauthenticated client can cause a denial of service.

Risk Assessment

An attacker can completely crash the MCP server, making it unavailable.

Recommendation

Update GitHub MCP Server to version 1.1.0 or later.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS