{"schema":"threatline.record/2","record":{"id":"CVE-2026-114613","aliases":["GHSA-j586-36cw-2gc2"],"summary":"MessagePack: Unbounded memory leak in msgpack C extension on strict_map_key validation failure","details":"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.","categories":["Runtimes & languages"],"product":"msgpack-python","vendor":"msgpack","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-114613","source_modified_at":"2026-10-23T21:08:06.271Z","fetched_at":"2026-10-23T21:10:45.942435Z","product":"msgpack-python","vendor":"msgpack","versions":[{"version":"< 1.2.3","status":"affected"}],"defaultStatus":null},{"source":"GitHub Advisory Database","source_url":"https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2","source_modified_at":"2026-10-22T18:19:07Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"pip","name":"msgpack"},"range":"= 1.2.2"}],"fixed_versions":[{"source":"GitHub Advisory Database","source_url":"https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2","source_modified_at":"2026-10-22T18:19:07Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"pip","name":"msgpack"},"version":"1.2.3"}],"cvss":7.5,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00339,"percentile":0.26116,"score_date":"2026-10-23"},"published_at":"2026-10-22T18:22:40.544Z","modified_at":"2026-10-23T21:08:06.271Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-114613","fetched_at":"2026-10-23T21:10:45.942435Z","source_modified_at":"2026-10-23T21:08:06.271Z"},{"source":"GitHub Advisory Database","url":"https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-22T18:19:07Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-114613","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","GitHub Advisory Database","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2","tags":["x_refsource_CONFIRM"]},{"source":"CVE List","url":"https://github.com/msgpack/msgpack-python/commit/620b0eb4c89cd72d4098564537624d9dbb2ce141","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/msgpack/msgpack-python/releases/tag/v1.2.3","tags":["x_refsource_MISC"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"yes","technical_impact":"partial","assessed_at":"2026-10-23T17:32:58.847580Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-23T21:08:06.271Z","content_hash":"ac1f3a329a02d59cc65b617d159b12282d6cddbe9edd62ce16354371dfebf79c"}}