{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-12039",
        "assignerOrgId": "686469e6-3ff6-451b-ab8b-cf5b9e89401e",
        "state": "PUBLISHED",
        "assignerShortName": "Docker",
        "dateReserved": "2026-06-11T19:23:44.967Z",
        "datePublished": "2026-06-18T13:48:14.682Z",
        "dateUpdated": "2026-08-13T13:33:35.581Z"
    },
    "containers": {
        "cna": {
            "affected": [
                {
                    "defaultStatus": "unaffected",
                    "platforms": [
                        "MacOS",
                        "Linux",
                        "Windows"
                    ],
                    "product": "Docker Sandboxes",
                    "vendor": "Docker",
                    "cpes": [
                        "cpe:2.3:a:docker:docker_sandboxes:*:*:*:*:*:*:*:*"
                    ],
                    "versions": [
                        {
                            "version": "0.13.0",
                            "status": "affected",
                            "lessThan": "0.33.0",
                            "versionType": "semver"
                        }
                    ]
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "Sophie Lemos"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "supportingMedia": [
                        {
                            "base64": false,
                            "type": "text/html",
                            "value": "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."
                        }
                    ],
                    "value": "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."
                }
            ],
            "impacts": [
                {
                    "capecId": "CAPEC-554",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "CAPEC-554 Functionality Bypass"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "version": "4.0",
                        "vectorString": "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",
                        "baseScore": 5.7,
                        "baseSeverity": "MEDIUM",
                        "attackVector": "LOCAL",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "LOW",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "valueDensity": "NOT_DEFINED",
                        "vulnerabilityResponseEffort": "NOT_DEFINED",
                        "providerUrgency": "NOT_DEFINED",
                        "exploitMaturity": "NOT_DEFINED"
                    },
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ]
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-923",
                            "description": "CWE-923: Improper Restriction of Communication Channel to Intended Endpoints",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "686469e6-3ff6-451b-ab8b-cf5b9e89401e",
                "shortName": "Docker",
                "dateUpdated": "2026-08-13T13:33:35.581Z"
            },
            "references": [
                {
                    "tags": [
                        "product"
                    ],
                    "url": "https://docs.docker.com/ai/sandboxes/"
                },
                {
                    "tags": [
                        "release-notes"
                    ],
                    "url": "https://github.com/docker/sbx-releases/releases/tag/v0.33.0"
                }
            ],
            "source": {
                "discovery": "EXTERNAL"
            },
            "title": "Docker Sandboxes network egress allowlist bypass via unfiltered DNS resolution"
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-06-18T15:00:00.773890Z",
                                "id": "CVE-2026-12039",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-06-18T15:00:24.095Z"
                }
            }
        ]
    }
}