What’s Vulnerable › Vulnerabilities

CVE-2026-50194: Steeltoe vulnerable to management-port isolation bypass via spoofed Host header

• Severity: high (CVSS 8.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-06-17 · updated 2026-06-22
• Weakness: CWE-288

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.

Affected products

• SteeltoeOSS Steeltoe.Management.Endpoint: before 4.2.0
• SteeltoeOSS Steeltoe.Management.EndpointCore: from 3.2.2, < 3.4.0

References

• https://github.com/SteeltoeOSS/Steeltoe/commit/4cbc352fe89ac2e6c609554e435ab28996fec5e9
• https://github.com/SteeltoeOSS/Steeltoe/commit/b7ca93c510aaa08d7e4ebec40ce20c5811c2c4b6
• https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-58f6-6rj2-3v8r

Get alerted when CVE-2026-50194 or the next vulnerability affects your stack