SSRF in Christianhelle Refitter
CVE-2026-63184
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.
Published .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Christianhelle Refitter — versions < 2.1.1
Weakness classification (CWE)
References
- github.com/christianhelle/refitter/security/advisories/GHSA-x6w4-f264-3vvr
- github.com/christianhelle/refitter/pull/1173
- github.com/christianhelle/refitter/commit/6ad20a3803561225100b0a4bb6b12f947d23d…
- github.com/christianhelle/refitter/releases/tag/2.1.1
- github.com/user-attachments/files/29395269/reproduce.sh
- github.com/user-attachments/files/29395271/maintainer-report.txt
- github.com/user-attachments/files/29395272/advisory.md
- github.com/user-attachments/files/29395283/reproduce.sh
- github.com/user-attachments/files/29395284/maintainer-report.txt
- github.com/user-attachments/files/29395285/advisory.md
Frequently asked questions
- What is CVE-2026-63184?
- CVE-2026-63184 is a high-severity vulnerability in Christianhelle Refitter, classified under Inclusion of Functionality from Untrusted Control Sphere. CVSS score: 7.1/10. Published 2026-10-30.
- How severe is CVE-2026-63184?
- High severity. CVSS v3 base score is 7.1 out of 10.