What is GHSA-G53W-W6MJ-HRPP?

GHSA-G53W-W6MJ-HRPP is a critical-severity improper authentication vulnerability in github.com/Kuadrant/mcp-gateway (go), affecting versions < 0.7.0. It is fixed in 0.7.0. The application does not adequately verify the identity of a user, device, or process before granting access.

Which versions of github.com/Kuadrant/mcp-gateway are affected by GHSA-G53W-W6MJ-HRPP?

github.com/Kuadrant/mcp-gateway (go) versions < 0.7.0 is affected.

Is there a fix for GHSA-G53W-W6MJ-HRPP?

Yes. GHSA-G53W-W6MJ-HRPP is fixed in 0.7.0. Upgrade to this version or later.

Is GHSA-G53W-W6MJ-HRPP exploitable, and should I be worried?

Whether GHSA-G53W-W6MJ-HRPP is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether GHSA-G53W-W6MJ-HRPP is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

GHSA-G53W-W6MJ-HRPP

Q: Which versions of github.com/Kuadrant/mcp-gateway are affected by GHSA-G53W-W6MJ-HRPP?

github.com/Kuadrant/mcp-gateway (go) versions < 0.7.0 is affected.

Q: Is there a fix for GHSA-G53W-W6MJ-HRPP?

Yes. GHSA-G53W-W6MJ-HRPP is fixed in 0.7.0. Upgrade to this version or later.

Q: Is GHSA-G53W-W6MJ-HRPP exploitable, and should I be worried?

Whether GHSA-G53W-W6MJ-HRPP is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether GHSA-G53W-W6MJ-HRPP is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix GHSA-G53W-W6MJ-HRPP?

Upgrade github.com/Kuadrant/mcp-gateway to 0.7.0 or later.

Summary

MCP Gateway: Authority-injection and JWT/session bypass via the unauthenticated router hair-pin "router-key" / "mcp-init-host" path

The MCP router (ext_proc) exposes an initialize-method code path that, when a
request carries an mcp-init-host header, bypasses the gateway JWT session
validator and rewrites the upstream :authority header to whatever the caller
chooses, gated only by a single shared header value (router-key). The shared
value is

a literal string (secret-api-key) baked into cmd/mcp-broker-router/main.go
as a fall-back default, and
in controller-managed deployments, a SHA-256 truncation of the
MCPGatewayExtension UID, a non-secret value visible to anyone with get
permission on the resource, and additionally exposed in argv because it is
passed to the broker-router container via --mcp-router-key=....

A request that satisfies the trivial header check is forwarded to any backend
listener registered with the gateway (including external services such as
api.githubcopilot.com when configured), bypassing both the broker (where the
signed x-mcp-authorized capability filter is enforced) and the gateway's
JWT-based session model.

Impact

The application does not adequately verify the identity of a user, device, or process before granting access. Typical impact: unauthorized access to functions or data reserved for authenticated parties.

Affected versions

github.com/Kuadrant/mcp-gateway (< 0.7.0)

Security releases

github.com/Kuadrant/mcp-gateway → 0.7.0 (go)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

Already deployed Kodem?

See it in your environment New to Kodem? Get a demo →

Remediation advice

Upgrade github.com/Kuadrant/mcp-gateway to 0.7.0 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is GHSA-G53W-W6MJ-HRPP? GHSA-G53W-W6MJ-HRPP is a critical-severity improper authentication vulnerability in github.com/Kuadrant/mcp-gateway (go), affecting versions < 0.7.0. It is fixed in 0.7.0. The application does not adequately verify the identity of a user, device, or process before granting access.
Which versions of github.com/Kuadrant/mcp-gateway are affected by GHSA-G53W-W6MJ-HRPP? github.com/Kuadrant/mcp-gateway (go) versions < 0.7.0 is affected.
Is there a fix for GHSA-G53W-W6MJ-HRPP? Yes. GHSA-G53W-W6MJ-HRPP is fixed in 0.7.0. Upgrade to this version or later.
Is GHSA-G53W-W6MJ-HRPP exploitable, and should I be worried? Whether GHSA-G53W-W6MJ-HRPP is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether GHSA-G53W-W6MJ-HRPP is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix GHSA-G53W-W6MJ-HRPP? Upgrade github.com/Kuadrant/mcp-gateway to 0.7.0 or later.