Refitter is a tool for generating a C# REST API client using the Refit library. Prior to 2.1.2, the header parameter name in `parameters[].name` with `in: header` is emitted verbatim into a Refit `[Header("<name>")]` attribute string without escaping quotation marks. An attacker-influenced OpenAPI description can pass default validation without `--skip-validation` and break out from the parameter-list position by closing the parameter and method syntax, attribute, interface, and namespace. The generated file can remain valid C# while containing a top-level file class with a `[ModuleInitializer]` method, which executes attacker code when the compiled assembly is loaded at application startup, even if the client is never called. Query `AliasAs` and enum/default value sinks are escaped; this flaw is in header-name attribute-string emission. The behavior was verified with Refitter 2.0.0 and .NET 8. This issue is fixed in version 2.1.2.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 8.6 · christianhelleNVD modified 2026-10-30 22:17
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 7
- https://github.com/christianhelle/refitter/security/advisories/GHSA-58x9-vjvp-6mx8 x_refsource_confirm
- https://github.com/christianhelle/refitter/pull/1178 x_refsource_misc
- https://github.com/christianhelle/refitter/commit/63a19b03699a9c267d6fab5f758ec26484db83a1 x_refsource_misc
- https://github.com/christianhelle/refitter/releases/tag/2.1.2 x_refsource_misc
- https://github.com/user-attachments/files/29395048/maintainer-report.txt x_refsource_misc
- https://github.com/user-attachments/files/29395050/make_spec.py x_refsource_misc
- https://github.com/user-attachments/files/29395051/reproduce.sh x_refsource_misc