Is CVE-2026-47427 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-47427 being exploited in the wild.

How severe is CVE-2026-47427?

High severity, with a CVSS score of 7.5, published 28 July 2026.

Which products and versions are affected?

Github-Mcp-Server < 1.1.0; github.com/github/github-mcp-server (Go) < 1.1.0, SEMVER:introduced=0,fixed=1.1.0.

Is there a fix for CVE-2026-47427?

Yes. github.com/github/github-mcp-server (Go): upgrade to 1.1.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-47427 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-47427?

Check whether you run Github-Mcp-Server or github.com/github/github-mcp-server (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-47427: GitHub MCP Server denial of service via nil pointer dereference in CompletionsHandler

Q: Which products and versions are affected?

Github-Mcp-Server < 1.1.0; github.com/github/github-mcp-server (Go) < 1.1.0, SEMVER:introduced=0,fixed=1.1.0.

Q: Is there a fix for CVE-2026-47427?

Yes. github.com/github/github-mcp-server (Go): upgrade to 1.1.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-47427 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-47427?

Check whether you run Github-Mcp-Server or github.com/github/github-mcp-server (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-47427 · Severity: high · CVSS 7.5 · Published 2026-07-28

GitHub MCP Server is a tool used to integrate GitHub data and functionality with AI models. A flaw in how the server handles specific requests allows an unauthenticated attacker to crash the service by sending a specially crafted message. This results in a total denial of service, preventing the AI tools from accessing GitHub data until the server is manually restarted.

Vendors: GitHub, Go.

Quick answers

Is CVE-2026-47427 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-47427 being exploited in the wild.
How severe is CVE-2026-47427?: High severity, with a CVSS score of 7.5, published 28 July 2026.
Which products and versions are affected?: Github-Mcp-Server < 1.1.0; github.com/github/github-mcp-server (Go) < 1.1.0, SEMVER:introduced=0,fixed=1.1.0.
Is there a fix for CVE-2026-47427?: Yes. github.com/github/github-mcp-server (Go): upgrade to 1.1.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-47427 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-47427?: Check whether you run Github-Mcp-Server or github.com/github/github-mcp-server (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/github/github-mcp-server (Go): upgrade to 1.1.0 or later
```
go get github.com/github/github-mcp-server@v1.1.0
```

Technical details

A vulnerability exists in the `CompletionsHandler` function within `pkg/github/server.go` of the GitHub MCP Server. The function attempts to access `params.Ref` without verifying if the pointer is nil. An attacker can trigger a Go runtime panic by sending a `completion/complete` JSON-RPC request that omits the `ref` field or contains empty parameters. Because this dereference occurs before authentication or token validation, any network-reachable client can crash the process. The issue is resolved in version 1.1.0 by implementing proper nil-guards on the request parameters.

Affected products

GitHub github-mcp-server < 1.1.0

Identifiers

CVE-2026-47427
GHSA-w4q6-qw23-4rg7
GO-2026-6118

Timeline

2026-02-21: disclosed: Initial report to GitHub Open Source Security
2026-05-19: patched: Fix merged into main branch
2026-05-28: patched: Version 1.1.0 released
2026-07-20: advisory: GitHub Security Advisory published
2026-07-28: advisory: NVD published CVE-2026-47427

References

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