Security advisory

{
  "id": "caa7f6ceabaca704f0cb94ab3d5793037bfcfeef3ef217dc86792d2275db6444",
  "url": "https://osv.dev/vulnerability/CVE-2021-21428",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-21428",
    "summary": "Openapi generator is a java tool which allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec. openapi-generator-online creates insecure temporary folders with File.createTempFile during the code generation process. The insecure temporary folders store the auto-generated files which can be read and appended to by any users on the system. The issue has been patched with `Files.createTempFile` and released in the v5.1.0 stable version.",
    "evidence": "osv:CVE-2021-21428",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2021-21428",
      "aliases": [
        "CVE-2021-21428",
        "GHSA-23x4-m842-fmwf"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/openapitools/openapi-generator",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "e023eaa8218da996140148161978953cc698d014"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:openapi-generator:openapi_generator:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "5.1.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v5.0.0",
            "v5.0.0-beta3",
            "v5.0.0-beta2",
            "v5.0.0-beta",
            "v4.3.1",
            "v4.3.0",
            "v4.2.3",
            "v4.2.2",
            "v4.2.1",
            "v4.2.0",
            "v4.1.0",
            "v4.0.3",
            "v4.0.2",
            "v4.0.1",
            "v4.0.0",
            "v4.0.0-beta3",
            "v4.0.0-beta2",
            "v3.0.1",
            "v3.0.0",
            "v2.3.1",
            "v2.3.0",
            "v2.2.3",
            "v2.2.2",
            "v2.2.1",
            "v2.2.0",
            "v2.1.6",
            "v2.1.5",
            "v2.1.4",
            "v2.1.3",
            "v2.1.2",
            "v2.1.0-M2",
            "v2.1.2-M1",
            "v2.1.1-M1",
            "v2.1.0-M1",
            "v2.0.18",
            "2.0.17",
            "swagger-codegen_2.9.1-2.0.1",
            "swagger-codegen_2.9.1-2.0.0",
            "swagger-codegen_2.9.1-1.1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-21428.json"
          }
        }
      ],
      "modified": "2026-10-20T10:55:20.220219288Z",
      "provider": "osv",
      "references": [
        "https://github.com/OpenAPITools/openapi-generator/pull/8788",
        "https://github.com/OpenAPITools/openapi-generator/security/advisories/GHSA-23x4-m842-fmwf"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-21428",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 387072,
  "published_at": "2021-05-10T19:15:08.06+00:00"
}