CVE-2020-1747
Estado: ModificadaCrítica (9.8)—
A vulnerability was discovered in the PyYAML library in versions before 5.3.1, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. An attacker could use this flaw to execute arbitrary code on the system by abusing the python/object/new constructor.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 5.44%
- Percentil entre todas las CVEs puntuadas: 93
- Fecha de la puntuación: 7/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (4)
CWE
- CWE-20
- CWE-20
Referencias
- http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00017.html
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00017.html
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1747
- https://github.com/yaml/pyyaml/pull/386
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7PPAS6C4SZRDQLR7C22A5U3QOLXY33JX/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K5HEPD7LEVDPCITY5IMDYWXUMX37VFMY/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MMQXSZXNJT6ERABJZAAICI3DQSQLCP3D/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WORRFHPQVAFKKXXWLSSW6XKUYLWM6CSH/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBJA3SGNJKCAYPSHOHWY3KBCWNM5NYK2/
- https://www.oracle.com/security-alerts/cpujul2022.html
- http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00017.html
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00017.html
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1747
- https://github.com/yaml/pyyaml/pull/386
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7PPAS6C4SZRDQLR7C22A5U3QOLXY33JX/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K5HEPD7LEVDPCITY5IMDYWXUMX37VFMY/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MMQXSZXNJT6ERABJZAAICI3DQSQLCP3D/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WORRFHPQVAFKKXXWLSSW6XKUYLWM6CSH/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBJA3SGNJKCAYPSHOHWY3KBCWNM5NYK2/
- https://www.oracle.com/security-alerts/cpujul2022.html
JSON original (NVD)
Mostrar
{
"id": "CVE-2020-1747",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 10,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C",
"authentication": "NONE",
"integrityImpact": "COMPLETE",
"accessComplexity": "LOW",
"availabilityImpact": "COMPLETE",
"confidentialityImpact": "COMPLETE"
},
"acInsufInfo": false,
"impactScore": 10,
"baseSeverity": "HIGH",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "secalert@redhat.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.8,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 3.9
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.8,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "secalert@redhat.com",
"affectedData": [
{
"vendor": "Red Hat",
"product": "PyYAML",
"versions": [
{
"status": "affected",
"version": "5.3.1"
}
]
}
]
}
],
"published": "2020-03-24T15:15:12.293",
"references": [
{
"url": "http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00017.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "secalert@redhat.com"
},
{
"url": "http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00017.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "secalert@redhat.com"
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1747",
"tags": [
"Issue Tracking",
"Patch",
"Third Party Advisory"
],
"source": "secalert@redhat.com"
},
{
"url": "https://github.com/yaml/pyyaml/pull/386",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "secalert@redhat.com"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7PPAS6C4SZRDQLR7C22A5U3QOLXY33JX/",
"source": "secalert@redhat.com"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K5HEPD7LEVDPCITY5IMDYWXUMX37VFMY/",
"source": "secalert@redhat.com"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MMQXSZXNJT6ERABJZAAICI3DQSQLCP3D/",
"source": "secalert@redhat.com"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WORRFHPQVAFKKXXWLSSW6XKUYLWM6CSH/",
"source": "secalert@redhat.com"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBJA3SGNJKCAYPSHOHWY3KBCWNM5NYK2/",
"source": "secalert@redhat.com"
},
{
"url": "https://www.oracle.com/security-alerts/cpujul2022.html",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "secalert@redhat.com"
},
{
"url": "http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00017.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00017.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1747",
"tags": [
"Issue Tracking",
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://github.com/yaml/pyyaml/pull/386",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7PPAS6C4SZRDQLR7C22A5U3QOLXY33JX/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K5HEPD7LEVDPCITY5IMDYWXUMX37VFMY/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MMQXSZXNJT6ERABJZAAICI3DQSQLCP3D/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WORRFHPQVAFKKXXWLSSW6XKUYLWM6CSH/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBJA3SGNJKCAYPSHOHWY3KBCWNM5NYK2/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://www.oracle.com/security-alerts/cpujul2022.html",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "secalert@redhat.com",
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
},
{
"type": "Secondary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability was discovered in the PyYAML library in versions before 5.3.1, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. An attacker could use this flaw to execute arbitrary code on the system by abusing the python/object/new constructor."
},
{
"lang": "es",
"value": "Se descubrió una vulnerabilidad en la biblioteca PyYAML versiones anteriores a 5.3.1, donde es susceptible a una ejecución de código arbitraria cuando procesa archivos YAML no seguros por medio del método full_load o con el cargador FullLoader. Las aplicaciones que usan la biblioteca para procesar entradas no seguras pueden ser vulnerables a este fallo. Un atacante podría usar este fallo para ejecutar código arbitrario en el sistema al violar el constructor python/object/new."
}
],
"lastModified": "2026-06-17T03:02:19.383",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:pyyaml:pyyaml:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "CF3AB645-B02B-41E0-B2E7-6AAC11ADDB34",
"versionEndExcluding": "5.3.1",
"versionStartIncluding": "5.1"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "97A4B8DF-58DA-4AB6-A1F9-331B36409BA3"
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "80F0FA5D-8D3B-4C0E-81E2-87998286AF33"
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "36D96259-24BD-44E2-96D9-78CE1D41F956"
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B620311B-34A3-48A6-82DF-6F078D7A4493"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:22.1.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "04E6C8E9-2024-496C-9BFD-4548A5B44E2E"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "secalert@redhat.com"
}