Is CVE-2026-63344 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-63344 being exploited in the wild.

How severe is CVE-2026-63344?

Informational severity, published 30 October 2026.

Which products and versions are affected?

Christian Helle Refitter prior to 2.1.2.

Is there a fix for CVE-2026-63344?

Yes: fixed in 2.1.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-63344 attacked?

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

Am I affected by CVE-2026-63344?

Check whether you run Christian Helle Refitter 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-2026-63344: Refitter code injection in generated Refit headers

CVE-2026-63344 · Severity: info · Published 2026-10-30

Refitter is a code generator that creates C# REST API clients. An attacker can craft a malicious OpenAPI specification with special characters in content-type declarations that inject arbitrary C# code into the generated client. When an application compiles and loads this generated code, the injected code executes automatically at startup, giving the attacker complete control over the application.

Technologies: Christian Helle Refitter. Vendors: Christian Helle.

Quick answers

Is CVE-2026-63344 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-63344 being exploited in the wild.
How severe is CVE-2026-63344?: Informational severity, published 30 October 2026.
Which products and versions are affected?: Christian Helle Refitter prior to 2.1.2.
Is there a fix for CVE-2026-63344?: Yes: fixed in 2.1.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-63344 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-63344?: Check whether you run Christian Helle Refitter 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

Fixed in: 2.1.2

Technical details

Refitter failed to escape quotation marks and other special characters when emitting OpenAPI content-type values into Refit [Headers] attribute strings. An attacker can break out of the attribute literal by including quote characters in a content-type key, inject a top-level C# class with a [ModuleInitializer] method, and achieve code execution when the generated assembly loads—no user interaction or client method calls required. The vulnerability affects Refitter prior to 2.1.2 and does not require --skip-validation to exploit.

Affected products

Christian Helle Refitter prior to 2.1.2

Timeline

2026-10-30: disclosed
2026-07-27: patched: Fix merged in PR #1178

References

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