Security advisory

{
  "id": "c63cf1ec580ec5a72c4ec00fb14259c503b68e5e8ad2b6d5def69cbb430b6dea",
  "url": "https://osv.dev/vulnerability/CVE-2020-23921",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-23921",
    "summary": "An issue was discovered in fast_ber through v0.4. yy::yylex() in asn_compiler.hpp has a heap-based buffer over-read.",
    "evidence": "osv:CVE-2020-23921",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2020-23921",
      "aliases": [
        "CVE-2020-23921"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/samuel-tyler/fast_ber",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "3aad811738443cc4e407e381a8ac700d6934e7b1"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:fast_ber_project:fast_ber:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "0.4"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.4",
            "v0.3",
            "0.3",
            "v0.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-23921.json"
          }
        }
      ],
      "modified": "2026-10-20T10:52:50.297663607Z",
      "provider": "osv",
      "references": [
        "https://cwe.mitre.org/data/definitions/126.html",
        "https://github.com/Samuel-Tyler/fast_ber/issues/30"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-23921",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 383921,
  "published_at": "2021-04-21T18:15:08.307+00:00"
}