---
id: CVE-2026-100347
title: kin-openapi is a Go project for handling OpenAPI files
summary: >-
  kin-openapi is a Go project for handling OpenAPI files. Prior to 0.145.0,
  openapi3filter.ValidationHandler uses the routers/legacy router, which passes
  an unsupported or non-canonical HTTP method for an existing static path to
  openapi3.P…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-20
  - CWE-248
vendor: getkin
product: kin-openapi
affected:
  - kin-openapi < 0.145.0
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T17:17:07.413'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100347'
references:
  - url: >-
      https://github.com/getkin/kin-openapi/commit/f1a5b523b82868d2d9be2e116b4e942892be72c3
    label: security-advisories@github.com
  - url: 'https://github.com/getkin/kin-openapi/releases/tag/v0.145.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/getkin/kin-openapi/security/advisories/GHSA-fh4f-47mf-f2gj
    label: security-advisories@github.com
  - url: >-
      https://github.com/getkin/kin-openapi/security/advisories/GHSA-fh4f-47mf-f2gj
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-15T16:21:25.376654Z'
ingestedAt: '2026-10-15T16:13:11.142Z'
---

## Overview

kin-openapi is a Go project for handling OpenAPI files. Prior to 0.145.0, openapi3filter.ValidationHandler uses the routers/legacy router, which passes an unsupported or non-canonical HTTP method for an existing static path to openapi3.PathItem.GetOperation. The default branch of GetOperation panics before authentication runs, so an unauthenticated remote client can repeatedly send methods such as PROPFIND or lowercase get to abort connections and generate stack-trace log growth. The specific panic requires an exact static path; a concrete path matched only by a templated route does not reach the same sink. This issue is fixed in version 0.145.0.

## Remediation

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