The Umbraco Heartcore headless client library uses a vulnerable Refit dependency package
Impact
The Heartcore headless client library depends on Refit to assist in making HTTP requests to Heartcore public APIs. Refit recently published an advisory regarding a CRLF injection vulnerability whereby it is possible for a malicious user to smuggle additional headers or potentially body content into a request.
This shouldn't affect Heartcore client library usage as the vulnerable method - HttpHeaders.TryAddWithoutValidation - is not used. However, since Refit is a transient dependency for applications using this library, then any users making direct use of Refit could be vulnerable.
Patches
The vulnerable version of Refit has been upgraded to a secure version, as of Umbraco.Headless.Client.Net version 1.5.0, available on Nuget.
Workarounds
If calling Refit from your own code, set any necessary HTTP headers without use of HttpHeaders.TryAddWithoutValidation.
References
See the original Refit advisory for further info.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| .NET (NuGet) | Umbraco.Headless.Client.Net | < 1.5.0 | 1.5.0 |
References
- Weakness (CWE)
CWE-1395, CWE-93- Platform
- .NET (NuGet)
- Package
Umbraco.Headless.Client.Net- Disclosed
- 13.01.2025
- Updated
- 11.10.2026 11:23
Sources and licenses
OSV / GitHub Advisory Database - GHSA-mgr7-5782-6jh9 - CC BY 4.0
Vulnerability history: Umbraco.Headless.Client.Net
All published vulnerabilities of this package (.NET (NuGet)), newest first. Shows whether this is a one-off slip or a package that needs watching.
This is the only known vulnerability of this package.
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