CVE-2026-63471
UnratedPublished 2026-11-03 ยท last changed 2026-11-03
The fix
We hold no Microsoft remediation data for CVE-2026-63471, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.
What it is
fastapi-code-generator creates FastAPI applications from OpenAPI files. Prior to 0.8.1, the generator inserts an OpenAPI path into a generated @app.get(...) route decorator as a single-quoted generated route string without escaping embedded quotes. An attacker-controlled or attacker-influenced OpenAPI path can close the string and inject a valid Python expression into the decorator argument. Syntax-breaking input only causes generation to fail, but syntactically valid generated code executes with the application's or CI process's privileges when the generated module is imported and the decorator is evaluated. This OpenAPI path sink is distinct from the project's separate operation-summary docstring and additional-response-key sinks. This issue is fixed in version 0.8.1.