Security advisory

{
  "id": "1ac0b65dd78abaec67e8ec0f7cb0d4362be1a3ab9887e32f99721e5b110ad2c2",
  "url": "https://osv.dev/vulnerability/CVE-2026-12244",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-12244",
    "summary": "If NSD is configured as secondary for a zone, the primary of that zone can crash NSD with an AXFR containing a DNS message with a special crafted SVCB RR with an rdata size of 65512, that let's an (uint16_t) variable that is used to allocate space needed for the RR wrap (because total size > 65535), causing a heap overflow. The attacker can perform a controlled (RCE class) head write of up to 65509 bytes",
    "evidence": "osv:CVE-2026-12244",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-12244",
      "aliases": [
        "CVE-2026-12244"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/nlnetlabs/nsd",
              "type": "GIT",
              "events": [
                {
                  "introduced": "5c760d0f00e282e1626cbadfc67e8bb11744f20b"
                },
                {
                  "fixed": "fc930b88cb4f628defae9835449065945bda7ddc"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.14.0"
                      },
                      {
                        "fixed": "4.14.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-12244.json"
          }
        }
      ],
      "modified": "2026-10-27T02:30:41.851814378Z",
      "provider": "osv",
      "references": [
        "https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2026-12244",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 460039,
  "published_at": "2026-06-25T07:16:44.9+00:00"
}