{"id":"CVE-2026-63344","title":"Refitter: C# source injection through OpenAPI content-type map keys","summary":"Refitter is a tool for generating a C# REST API client using the Refit library. Prior to 2.1.2, content-type keys in the content maps of `requestBody/responses` are emitted verbatim into a Refit `[Headers(\"Accept: <ct>\", \"Content-Type: <…","severity":"high","cvss":8.6,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","cvssSource":"cna","cwe":["CWE-94","CWE-116"],"vendor":"christianhelle","product":"refitter","affected":["refitter < 2.1.2"],"published":"2026-10-30","updated":"2026-10-30","sourceUpdated":"2026-10-30T22:15:27.846Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-63344","references":[{"url":"https://github.com/christianhelle/refitter/security/advisories/GHSA-p32v-8v8j-j534","label":"https://github.com/christianhelle/refitter/security/advisories/GHSA-p32v-8v8j-j534"},{"url":"https://github.com/christianhelle/refitter/pull/1178","label":"https://github.com/christianhelle/refitter/pull/1178"},{"url":"https://github.com/christianhelle/refitter/commit/ab4d8e439d6f0ee82ad49ee15323978d70fe5a67","label":"https://github.com/christianhelle/refitter/commit/ab4d8e439d6f0ee82ad49ee15323978d70fe5a67"},{"url":"https://github.com/christianhelle/refitter/releases/tag/2.1.2","label":"https://github.com/christianhelle/refitter/releases/tag/2.1.2"},{"url":"https://github.com/user-attachments/files/29394848/reproduce.sh","label":"https://github.com/user-attachments/files/29394848/reproduce.sh"},{"url":"https://github.com/user-attachments/files/29394851/maintainer-report.txt","label":"https://github.com/user-attachments/files/29394851/maintainer-report.txt"},{"url":"https://github.com/user-attachments/files/29394853/make_spec.py","label":"https://github.com/user-attachments/files/29394853/make_spec.py"}],"tags":["cve.org"],"epss":0.0035,"epssPercentile":0.28833,"ingestedAt":"2026-11-05T16:24:31.479Z","slug":"CVE-2026-63344","body":"## Overview\n\nRefitter is a tool for generating a C# REST API client using the Refit library. Prior to 2.1.2, content-type keys in the content maps of `requestBody/responses` are emitted verbatim into a Refit `[Headers(\"Accept: <ct>\", \"Content-Type: <ct>\")]` attribute string without escaping quotation marks. A crafted content-type key in an attacker-influenced OpenAPI description survives default validation without `--skip-validation`, breaks out of the attribute string and enclosing interface and namespace, and can introduce a top-level file class while leaving valid generated C#. A `[ModuleInitializer]` method in that class executes attacker code when the generated assembly is loaded at application startup, without requiring a call to the client. The behavior was verified with Refitter 2.0.0 and .NET 8. This issue is fixed in version 2.1.2.\n\n## Affected\n\n- `refitter < 2.1.2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":47,"depthScoreParts":{"impact":47.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}