Security advisory

{
  "id": "3cab9693f19aafbe65648202448d458fc1a60e0edee05e5455429fd318882b51",
  "url": "https://osv.dev/vulnerability/CVE-2021-3404",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-3404",
    "summary": "In ytnef 1.9.3, the SwapWord function in lib/ytnef.c allows remote attackers to cause a denial-of-service (and potentially code execution) due to a heap buffer overflow which can be triggered via a crafted file.",
    "evidence": "osv:CVE-2021-3404",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2021-3404",
      "aliases": [
        "CVE-2021-3404"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/yeraze/ytnef",
              "type": "GIT",
              "events": [
                {
                  "introduced": "d9b2f01d125c9b178f7a00ec397cc2a9f258e8e1"
                },
                {
                  "last_affected": "d9b2f01d125c9b178f7a00ec397cc2a9f258e8e1"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:ytnef_project:ytnef:1.9.3:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.9.3"
                      },
                      {
                        "last_affected": "1.9.3"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.9.3",
            "v1.9.3"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-3404.json"
          }
        }
      ],
      "modified": "2026-10-20T10:54:44.902876726Z",
      "provider": "osv",
      "references": [
        "https://bugzilla.redhat.com/show_bug.cgi?id=1926965",
        "https://github.com/Yeraze/ytnef/issues/86"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*"
            ],
            "vendor_product": "fedoraproject:fedora",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "33"
                  },
                  {
                    "last_affected": "33"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          },
          {
            "cpes": [
              "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*"
            ],
            "vendor_product": "redhat:enterprise_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "7.0"
                  },
                  {
                    "last_affected": "7.0"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2021-3404",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 386065,
  "published_at": "2021-03-04T22:15:14.657+00:00"
}