CVE-2026-47427 (GCVE-0-2026-47427)
Vulnerability from cvelistv5 – Published: 2026-07-28 15:32 – Updated: 2026-07-28 17:31
VLAI
EPSS
VEX
Title
GitHub MCP Server: Nil Pointer Dereference DoS in completion/complete Handler
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.
Severity
7.5 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-28 17:31 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/github/github-mcp-server/secur… | x_refsource_CONFIRM |
| https://github.com/github/github-mcp-server/pull/2502 | x_refsource_MISC |
| https://github.com/github/github-mcp-server/commi… | x_refsource_MISC |
| https://github.com/github/github-mcp-server/relea… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| github | github-mcp-server |
Affected:
< 1.1.0
|
guessed |
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