---
id: CVE-2026-63471
title: >-
  fastapi-code-generator: Import-time RCE via route path -> unescaped
  @app.get('...') decorator
summary: >-
  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
  embed…
severity: critical
cvss: 9.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-94
  - CWE-116
vendor: koxudaxi
product: fastapi-code-generator
affected:
  - fastapi-code-generator < 0.8.1
published: '2026-11-03'
updated: '2026-11-03'
sourceUpdated: '2026-11-03T19:18:44.111Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-63471'
references:
  - url: >-
      https://github.com/koxudaxi/fastapi-code-generator/security/advisories/GHSA-p2mm-64f6-gmpp
    label: >-
      https://github.com/koxudaxi/fastapi-code-generator/security/advisories/GHSA-p2mm-64f6-gmpp
  - url: >-
      https://github.com/koxudaxi/fastapi-code-generator/commit/49301dbdb82170d7f50877419d994b05cb1fa2bc
    label: >-
      https://github.com/koxudaxi/fastapi-code-generator/commit/49301dbdb82170d7f50877419d994b05cb1fa2bc
  - url: >-
      https://github.com/koxudaxi/fastapi-code-generator/commit/b3b9bd66e0b0c4d8c686fda700258104615a1332
    label: >-
      https://github.com/koxudaxi/fastapi-code-generator/commit/b3b9bd66e0b0c4d8c686fda700258104615a1332
  - url: 'https://github.com/koxudaxi/fastapi-code-generator/releases/tag/0.8.1'
    label: 'https://github.com/koxudaxi/fastapi-code-generator/releases/tag/0.8.1'
tags:
  - cve.org
epss: 0.00312
epssPercentile: 0.24264
ingestedAt: '2026-11-05T20:33:06.395Z'
---

## Overview

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.

## Affected

- `fastapi-code-generator < 0.8.1`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.