CVE-2026-32874

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Versions 5.4.0 through 5.11.0 contain an accumulating memory leak in JSON parsing large (outside of the range [-2^63, 2^64 - 1]) integers. The leaked memory is a copy of the string form of the integer plus an additional NULL byte. The leak occurs irrespective of whether the integer parses successfully or is rejected due to having more than sys.get_int_max_str_digits() digits, meaning that any sized leak per malicious JSON can be achieved provided that there is no limit on the overall size of the payload. Any service that calls ujson.load()/ujson.loads()/ujson.decode() on untrusted inputs is affected and vulnerable to denial of service attacks. This issue has been fixed in version 5.12.0."}, {"lang": "es", "value": "UltraJSON es un codificador y decodificador JSON r\u00e1pido escrito en C puro con enlaces para Python 3.7+. Las versiones 5.4.0 a 5.11.0 contienen una fuga de memoria acumulativa al analizar JSON enteros grandes (fuera del rango [-2^63, 2^64 - 1]). La memoria filtrada es una copia de la forma de cadena del entero m\u00e1s un byte NULL adicional. La fuga ocurre independientemente de si el entero se analiza con \u00e9xito o es rechazado por tener m\u00e1s d\u00edgitos que sys.get_int_max_str_digits(), lo que significa que se puede lograr una fuga de cualquier tama\u00f1o por JSON malicioso siempre que no haya un l\u00edmite en el tama\u00f1o total de la carga \u00fatil. Cualquier servicio que llame a ujson.load()/ujson.loads()/ujson.decode() en entradas no confiables se ve afectado y es vulnerable a ataques de denegaci\u00f3n de servicio. Este problema ha sido solucionado en la versi\u00f3n 5.12.0."}], "id": "CVE-2026-32874", "lastModified": "2026-07-15T02:20:01.790", "metrics": {"cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}, {"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-32874", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-03-20T16:36:00.746519Z", "version": "2.0.3"}}]}, "published": "2026-03-20T02:16:35.703", "references": [{"source": "security-advisories@github.com", "tags": ["Patch"], "url": "https://github.com/ultrajson/ultrajson/commit/4baeb950df780092bd3c89fc702a868e99a3a1d2"}, {"source": "security-advisories@github.com", "tags": ["Product", "Release Notes"], "url": "https://github.com/ultrajson/ultrajson/releases/tag/5.12.0"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/ultrajson/ultrajson/security/advisories/GHSA-wgvc-ghv9-3pmm"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/security/cve/CVE-2026-32874"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2449411"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32874.json"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-401"}], "source": "security-advisories@github.com", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-772"}], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "type": "Secondary"}]}

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