CVE-2026-50194 Steeltoe vulnerable to management-port isolation bypass via spoofed Host header
Attackers can bypass management endpoint port isolation by spoofing the Host header, exposing sensitive actuator endpoints in Steeltoe cloud-native applications.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-50194?
CVE-2026-50194 is a high-severity vulnerability in SteeltoeOSS Steeltoe.Management.Endpoint, published on 17 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. When Steeltoe management endpoints versions 3.2.2 through 3.3.0 and 4.1.0 are configured to listen on an alternate port (`Management:Endpoints:Port` is configured), the middleware responsible for restricting access to the endpoints uses the `Host` HTTP header rather than the actual network socket port. Versions 3.4.0 and 4.2.0 patch the issue. If an immediate upgrade to a patched version is not possible, add explicit ASP.NET Core authorization (`RequireAuthorization`) to all sensitive actuator endpoints as a defense-in-depth measure independent of port isolation and/or configure the reverse proxy or load balancer to enforce the `Host` header value and prevent clients from setting an arbitrary port.
Which versions are affected by CVE-2026-50194?
4 open source packages ship an affected version, including Steeltoe.Management.Endpoint and Steeltoe.Management.EndpointCore.
| Package | Affected | Fixed in |
|---|---|---|
Steeltoe.Management.Endpoint NuGet | All versions | 4.2.0 |
Steeltoe.Management.Endpoint NuGet | All versions | 4.2.0 |
Steeltoe.Management.EndpointCore NuGet | From 3.2.2 | 3.4.0 |
Steeltoe.Management.EndpointCore NuGet | From 3.2.2 | 3.4.0 |
How do I fix CVE-2026-50194?
Upgrade Steeltoe.Management.Endpoint to 4.2.0 or later.
Is CVE-2026-50194 being exploited?
There is no known exploitation of CVE-2026-50194 in the wild and no public exploit code.
Sources
Also known as GHSA-58f6-6rj2-3v8r.