{"api_version":"1","generated_at":"2026-10-23T04:08:28+00:00","cve":"CVE-2026-114613","urls":{"html":"https://cve.report/CVE-2026-114613","api":"https://cve.report/api/cve/CVE-2026-114613.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-114613","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-114613"},"summary":{"title":"MessagePack: Unbounded memory leak in msgpack C extension on strict_map_key validation failure","description":"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. 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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.","Type":"Description","Title":"MessagePack: Unbounded memory leak in msgpack C extension on str"}]}}}