{"id":"CVE-2026-114613","revision":"80ceb745d4b5490f9ed54ee6049c3c8a","records":[{"revision":"80ceb745d4b5490f9ed54ee6049c3c8a","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-114613","aliases":[],"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. The pure-Python fallback does not exhibit this leak in the reported tests. This issue is fixed in version 1.2.3.","state":0,"publishedAt":"2026-10-22T18:22:40.544+00:00","modifiedAt":"2026-10-22T18:22:40.544+00:00","affected":[{"ecosystem":"Vendor product","name":"msgpack-python","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"msgpack\",\n                    \"product\": \"msgpack-python\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 1.2.3\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2","https://github.com/msgpack/msgpack-python/commit/620b0eb4c89cd72d4098564537624d9dbb2ce141","https://github.com/msgpack/msgpack-python/releases/tag/v1.2.3"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-114613","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-114613","identifiers":["CVE-2026-114613"]},"retained":false,"historicalAffected":[]}],"coverage":[]}