{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0.13.0"
              },
              {
                "fixed": "0.33.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "e4809b108ff941fbd3dc8ab1edd8755af78ddc07"
            }
          ],
          "repo": "https://github.com/docker/sbx-releases",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Docker",
    "cwe_ids": [
      "CWE-923"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12039.json"
  },
  "details": "Docker Sandboxes (sbx) enforces an HTTP/S-only egress allowlist but does not apply it to DNS resolution: the per-network embedded DNS server forwards any queried name to the host resolver whenever the network is internet-connected, without consulting the policy. A workload inside a sandbox, which the threat model treats as untrusted, can therefore encode data into DNS labels for an attacker-controlled domain and exfiltrate it through a DNS covert channel, bypassing the configured allowlist.",
  "id": "CVE-2026-12039",
  "modified": "2026-07-08T05:37:38.839865357Z",
  "published": "2026-06-18T13:48:14.682Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://docs.docker.com/ai/sandboxes/"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12039.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/docker/sbx-releases/releases/tag/v0.33.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-12039"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Docker Sandboxes network egress allowlist bypass via unfiltered DNS resolution"
}