CVE-2026-63184
HighCVSS 7.1Exploitation Probability (EPSS)
Low risk35th percentile - higher than 35% of all known CVEs
Summary
In the refitter dotnet tool prior to 2.1.1, NJsonSchema is invoked with unsafe $ref resolution defaults when generating Refit interfaces from attacker-controlled OpenAPI descriptions. Remote http(s) references cause requests from the developer or CI host and inline untrusted content, while absolute local paths and ../ traversal allow arbitrary local-file disclosure. The chain stops at SSRF, remote file inclusion, and local file inclusion, not code execution.
Risk Assessment
It may lead to disclosure of local files on the developer or CI host and to SSRF requests from trusted infrastructure. The risk affects code generation from untrusted OpenAPI specifications.
Recommendation
Update refitter to version 2.1.1 or later. Generate clients only from trusted OpenAPI specifications and avoid processing untrusted descriptions in CI.
Other vulnerabilities in Refitter
See all- CVE-2026-63346High
In Refitter 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 of the parameter-list position, generating valid C# with a file class and [ModuleInitializer] method that executes attacker code when the compiled assembly is loaded.
- CVE-2026-63345High
Refitter prior to 2.1.2 emits OpenAPI `paths` object keys verbatim into Refit route attributes without escaping quotation marks. A crafted single-line, slash-prefixed path can close the attribute, interface, and namespace and inject a top-level class with a `[ModuleInitializer]` method that executes attacker code when the generated assembly is loaded. The issue is fixed in version 2.1.2.
- CVE-2026-63344High
Refitter prior to 2.1.2 emits content-type keys from `requestBody/responses` content maps verbatim into a Refit `[Headers(...)]` attribute string without escaping quotation marks. A crafted content-type key in an OpenAPI description can break out of the attribute, interface, and namespace and inject a top-level class with a `[ModuleInitializer]` method that executes attacker code when the generated assembly is loaded. The issue is fixed in version 2.1.2.
Original NVD description (English source)
Refitter is a tool for generating a C# REST API client using the Refit library. Prior to 2.1.1, the `refitter` dotnet tool invokes `NJsonSchema` with unsafe defaults for `$ref` resolution when generating Refit interfaces and contracts from attacker-controlled or attacker-influenced OpenAPI descriptions. Remote `http(s)` references cause requests from the developer or CI host and inline untrusted remote schema content into generated output. Absolute local file paths and relative `../` traversal outside the input directory also resolve and inline local content, permitting arbitrary local-file disclosure. The demonstrated chain stops at server-side request forgery, remote file inclusion, and local file inclusion, not code execution: Refit sets the base URL at runtime, enum values use verbatim-string doubling, and string defaults are escaped. This issue is fixed in version 2.1.1.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS