{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "2.0"
              },
              {
                "last_affected": "4.0.0"
              },
              {
                "introduced": "0"
              },
              {
                "fixed": "4.0.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "4f904e0dea407e3cc47c29cb4bf717eecb2921c1"
            },
            {
              "fixed": "434bccd609f2a3e90d6bb95c458621898bc6a508"
            }
          ],
          "repo": "https://github.com/mrubyc/mrubyc",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-476"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86547.json"
  },
  "details": "mrubyc through 4.0.0 contains a null pointer dereference vulnerability in the op_enter() handler in src/vm.c when processing untrusted bytecode. Attackers can craft malicious .mrb bytecode files with OP_ENTER instructions at the top level to crash the embedding application and cause denial of service.",
  "id": "CVE-2026-86547",
  "modified": "2026-09-12T03:30:52.341775368Z",
  "published": "2026-09-09T10:07:25.743Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86547.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86547"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/mrubyc-through-4.0.0-null-pointer-dereference-via-op-enter"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/mrubyc/mrubyc"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/mrubyc/mrubyc/blob/4261cf5e5ae5579e3110dab98a04b91c7d919429/src/vm.c#L1534"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/mrubyc/mrubyc/blob/release4.0.0/src/vm.c#L1537"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "mrubyc through 4.0.0 NULL Pointer Dereference via OP_ENTER"
}