CVE-2026-63345：Refitter 透過 OpenAPI 路徑鍵導致 C# 原始碼注入
CVE-2026-63345 - Refitter: C# source injection through OpenAPI path keys
CVE-2026-63345：Refitter 2.0.0 允許攻擊者在 OpenAPI paths 鍵中注入特殊字元，造成 [ModuleInitializer] 執行任意程式碼。
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.
Impact
Affected Products
The following products are affected by CVE-2026-63345
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
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are
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No affected product recoded yet
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | [email protected] |
Update Refitter to version 2.1.2 or later to fix path injection vulnerabilities in route attributes.
- Update Refitter to version 2.1.2 or later.
- Review generated API client code for malicious injection.
- Ensure proper input validation for API paths.
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While CVE identifies
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weaknesses that can lead to vulnerabilities. CVE-2026-63345 is
associated with the following CWEs:
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weaknesses.
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The following table lists the changes that have been made to the
CVE-2026-63345 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
十月. 30, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-94 Added CWE CWE-1116 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/63xxx/CVE-2026-63345.json">CVE-2026-63345</a> Added Reference https://github.com/christianhelle/refitter/commit/793d2632899c2022511dfc15e30725ef69073973 Added Reference https://github.com/christianhelle/refitter/pull/1178 Added Reference https://github.com/christianhelle/refitter/releases/tag/2.1.2 Added Reference https://github.com/christianhelle/refitter/security/advisories/GHSA-3fhm-p725-h3g3 Added Reference https://github.com/user-attachments/files/29395228/maintainer-report.txt Added Reference https://github.com/user-attachments/files/29395229/make_spec.py Added Reference https://github.com/user-attachments/files/29395230/reproduce.sh
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.