{"id":"CVE-2026-63184","aliases":["EUVD-2026-114521","GHSA-x6w4-f264-3vvr"],"status":"published","title":"Refitter: Unrestricted OpenAPI references permit build-host SSRF and file inclusion","description":"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.","severity":{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00411,"percentile":0.35719,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-829","CWE-918"],"published":"2026-10-30T21:49:06Z","modified":"2026-11-04T02:30:47Z","products":[{"vendor":"christianhelle","product":"refitter"}],"references":[{"url":"https://github.com/christianhelle/refitter/security/advisories/GHSA-x6w4-f264-3vvr","tags":["x_refsource_CONFIRM","exploit","advisory"]},{"url":"https://github.com/christianhelle/refitter/pull/1173","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/christianhelle/refitter/commit/6ad20a3803561225100b0a4bb6b12f947d23db7b","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/christianhelle/refitter/releases/tag/2.1.1","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/user-attachments/files/29395269/reproduce.sh","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/user-attachments/files/29395271/maintainer-report.txt","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/user-attachments/files/29395272/advisory.md","tags":["x_refsource_MISC","advisory"]},{"url":"https://github.com/user-attachments/files/29395283/reproduce.sh","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/user-attachments/files/29395284/maintainer-report.txt","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/user-attachments/files/29395285/advisory.md","tags":["x_refsource_MISC","advisory"]},{"url":"https://github.com/user-attachments/files/29395286/listener.py","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/user-attachments/files/29395288/make_spec.py","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63184.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63184","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-63184","title":"Refitter: Unrestricted OpenAPI references permit build-host SSRF and file inclusion","description":"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.","status":"published","published":"2026-10-30T21:49:06.793Z","modified":"2026-11-02T14:43:07.417Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-829","CWE-918"],"updated_at":"2026-11-02T18:00:08.034842Z"}],"euvd":[{"id":"EUVD-2026-114521","description":"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 `$ref` resolution when generating Refit interfaces and contracts from attacker-controlled or attacker-influenced OpenAPI descriptions. Remote `http(s)` references cause requests from the developer or CI host and inline untrusted remote schema content into generated output. Absolute local file paths and relative `../` traversal outside the input directory also resolve and inline local content, permitting arbitrary local-file disclosure. The demonstrated chain stops at server-side request forgery, remote file inclusion, and local file inclusion, not code execution: Refit sets the base URL at runtime, enum values use verbatim-string doubling, and string defaults are escaped. This issue is fixed in version 2.1.1.","status":"published","published":"2026-10-30T21:49:06Z","modified":"2026-11-02T14:43:07Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high"}],"updated_at":"2026-11-02T16:58:44.835214Z"}],"nvd":[{"id":"CVE-2026-63184","description":"Refitter is a tool for generating a C# REST API client using the Refit library. Prior to 2.1.1, the `refitter` dotnet tool invokes `NJsonSchema` with unsafe defaults for `$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.","status":"published","published":"2026-10-30T22:16:58.447Z","modified":"2026-11-02T19:35:33.347Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-829","CWE-918"],"updated_at":"2026-11-03T00:02:42.364722Z"}],"osv":[{"id":"CVE-2026-63184","title":"Refitter: Unrestricted OpenAPI references permit build-host SSRF and file inclusion","description":"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.","status":"published","published":"2026-10-30T21:49:06.793Z","modified":"2026-11-04T02:30:47.762952591Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high"}],"cwes":["CWE-829","CWE-918"],"updated_at":"2026-11-04T02:54:44.889498Z"}]}}