CVE-2026-63345 (GCVE-0-2026-63345)

Vulnerability from cvelistv5 – Published: 2026-10-30 22:13 – Updated: 2026-11-02 17:58
VLAI
Title
Refitter: C# source injection through OpenAPI path keys
Summary
Refitter is a tool for generating a C# REST API client using the Refit library. Prior to 2.1.2, OpenAPI `paths`-object keys are emitted verbatim into Refit route attributes such as `[Get("<path>")]` without escaping quotation marks or restricting characters. An attacker-influenced single-line, slash-prefixed path survives default validation without `--skip-validation` and can close the attribute string, interface, and namespace while introducing a top-level file class and reopening the generated structure to keep valid C#. A `[ModuleInitializer]` method executes attacker code when an application compiles and loads the generated assembly at startup, even without calling the generated client. The enum and default value sinks are escaped and are not the vulnerable path-emission sink. The behavior was verified on Refitter 2.0.0 with .NET 8. This issue is fixed in version 2.1.2.
Severity
8.6 (High)
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
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-02 17:09 UTC
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
  • CWE-1116 - Inaccurate Comments
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8016 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
christianhelle refitter Affected: < 2.1.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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