Description
fastapi-code-generator creates FastAPI applications from OpenAPI files. Prior to 0.8.1, the generator inserts Operation.summary into a generated route-handler docstring as a triple-double-quoted string without escaping embedded triple quotes. An attacker-controlled or attacker-influenced operation summary can close the docstring and inject a valid Python expression statement into the handler body. Syntax-breaking input only causes generation to fail, but syntactically valid generated code executes with the server process's privileges when the affected route handler is called. This call-time route-handler docstring sink is distinct from the project's separate import-time route-path and additional-response-key sinks. This issue is fixed in version 0.8.1.
Published: 2026-11-03
Score: 9.3 Critical
EPSS: n/a
KEV: No
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Tue, 03 Nov 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Tue, 03 Nov 2026 19:30:00 +0000

Type Values Removed Values Added
Description fastapi-code-generator creates FastAPI applications from OpenAPI files. Prior to 0.8.1, the generator inserts Operation.summary into a generated route-handler docstring as a triple-double-quoted string without escaping embedded triple quotes. An attacker-controlled or attacker-influenced operation summary can close the docstring and inject a valid Python expression statement into the handler body. Syntax-breaking input only causes generation to fail, but syntactically valid generated code executes with the server process's privileges when the affected route handler is called. This call-time route-handler docstring sink is distinct from the project's separate import-time route-path and additional-response-key sinks. This issue is fixed in version 0.8.1.
Title fastapi-code-generator: Call-time RCE via operation summary -> unescaped route-handler docstring
Weaknesses CWE-116
CWE-94
References
Metrics cvssV4_0

{'score': 9.3, 'vector': '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'}

Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-11-03T19:34:47.499Z

Reserved: 2026-07-16T21:37:45.769Z

Link: CVE-2026-63470

cve-icon Vulnrichment

Updated: 2026-11-03T19:34:43.036Z

cve-icon NVD

Status : Deferred

Published: 2026-11-03T20:18:15.590

Modified: 2026-11-03T20:31:38.783

Link: CVE-2026-63470

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-11-03T20:45:01Z

Weaknesses
  • CWE-116

    Improper Encoding or Escaping of Output

  • CWE-94

    Improper Control of Generation of Code ('Code Injection')