CVE-2026-63184

high

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.

References

https://github.com/user-attachments/files/29395288/make_spec.py

https://github.com/user-attachments/files/29395286/listener.py

https://github.com/user-attachments/files/29395285/advisory.md

https://github.com/user-attachments/files/29395284/maintainer-report.txt

https://github.com/user-attachments/files/29395283/reproduce.sh

https://github.com/user-attachments/files/29395272/advisory.md

https://github.com/user-attachments/files/29395271/maintainer-report.txt

https://github.com/user-attachments/files/29395269/reproduce.sh

https://github.com/christianhelle/refitter/security/advisories/GHSA-x6w4-f264-3vvr

https://github.com/christianhelle/refitter/releases/tag/2.1.1

https://github.com/christianhelle/refitter/pull/1173

https://github.com/christianhelle/refitter/commit/6ad20a3803561225100b0a4bb6b12f947d23db7b

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-114521

Details

Source: Mitre, NVD

Published: 2026-10-30

Updated: 2026-10-30

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:P/A:N

Severity: High

CVSS v3

Base Score: 7.1

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N

Severity: High

EPSS

EPSS: 0.00411