{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-114613",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-10-21T20:34:25.599Z",
        "datePublished": "2026-10-22T18:22:40.544Z",
        "dateUpdated": "2026-10-22T18:22:40.544Z"
    },
    "containers": {
        "cna": {
            "title": "MessagePack: Unbounded memory leak in msgpack C extension on strict_map_key validation failure",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-401",
                            "lang": "en",
                            "description": "CWE-401: Missing Release of Memory after Effective Lifetime",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2"
                },
                {
                    "name": "https://github.com/msgpack/msgpack-python/commit/620b0eb4c89cd72d4098564537624d9dbb2ce141",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/msgpack/msgpack-python/commit/620b0eb4c89cd72d4098564537624d9dbb2ce141"
                },
                {
                    "name": "https://github.com/msgpack/msgpack-python/releases/tag/v1.2.3",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/msgpack/msgpack-python/releases/tag/v1.2.3"
                }
            ],
            "affected": [
                {
                    "vendor": "msgpack",
                    "product": "msgpack-python",
                    "versions": [
                        {
                            "version": "< 1.2.3",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-10-22T18:22:40.544Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "MessagePack is the serializer implementation for Python msgpack.org. Prior to 1.2.3, the msgpack-python C extension (msgpack._cmsgpack) leaks a decoded map value when deserialization rejects a key with strict_map_key=True (the default). Repeated malformed inputs can cause unbounded process memory growth and denial of service in applications that deserialize attacker-controlled MessagePack data. Both unpackb() and the streaming Unpacker API are affected. The pure-Python fallback does not exhibit this leak in the reported tests. This issue is fixed in version 1.2.3."
                }
            ],
            "source": {
                "advisory": "GHSA-j586-36cw-2gc2",
                "discovery": "UNKNOWN"
            }
        }
    }
}