Security advisory

{
  "id": "a06309ae5a58de1e7a9d7878b6cc7578a24ae0f97f23282942f947b5a6a20f1a",
  "url": "https://osv.dev/vulnerability/CVE-2019-9720",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2019-9720",
    "summary": "A stack-based buffer overflow in the subtitle decoder in Libav 12.3 allows attackers to corrupt the stack via a crafted video file in Matroska format, because srt_to_ass in libavcodec/srtdec.c misuses snprintf.",
    "evidence": "osv:CVE-2019-9720",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2019-9720",
      "aliases": [
        "CVE-2019-9720"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/libav/libav",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "df744e3cf66548c9167ea857104a29d2ea92819e"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:libav:libav:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "12.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v12.3",
            "v12.1",
            "v12",
            "v12_beta1",
            "v12_alpha2",
            "v12_alpha1",
            "v12_dev0",
            "v11_beta1",
            "v11_alpha2",
            "v11_alpha1",
            "v10_beta1",
            "v11_dev0",
            "dev14.2",
            "v10_alpha2",
            "v10_alpha1",
            "v9",
            "v9_beta3",
            "v9_beta2",
            "v9_beta1",
            "v0.8",
            "v0.8b2",
            "v0.8b1",
            "v0.7",
            "v0.7rc1",
            "v0.7b2",
            "v0.7b1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-9720.json"
          }
        }
      ],
      "modified": "2026-10-20T10:51:43.847460355Z",
      "provider": "osv",
      "references": [
        "https://lgtm.com/security/",
        "https://github.com/libav/libav/blob/df744e3cf66548c9167ea857104a29d2ea92819e/libavcodec/srtdec.c#L161"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2019-9720",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 382825,
  "published_at": "2019-09-19T21:15:10.58+00:00"
}