{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.1.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "c88d2ecdd3bb07f7bdd75296e3ee676febf14f58"
            },
            {
              "fixed": "c5be4b09c2e26e9c6adbc936b5fc661306852ebf"
            }
          ],
          "repo": "https://github.com/github/github-mcp-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-w4q6-qw23-4rg7"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-476"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47427.json"
  },
  "details": "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.",
  "id": "CVE-2026-47427",
  "modified": "2026-08-01T03:32:57.292523410Z",
  "published": "2026-07-28T15:32:27.294Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/github/github-mcp-server/releases/tag/v1.1.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47427.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/github/github-mcp-server/security/advisories/GHSA-w4q6-qw23-4rg7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-47427"
    },
    {
      "type": "FIX",
      "url": "https://github.com/github/github-mcp-server/commit/c88d2ecdd3bb07f7bdd75296e3ee676febf14f58"
    },
    {
      "type": "FIX",
      "url": "https://github.com/github/github-mcp-server/pull/2502"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "GitHub MCP Server: Nil Pointer Dereference DoS in completion/complete Handler"
}