CVE-2017-20285
YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes.
A perl/hash:Class tag blesses a hash into the class it names. The document supplies the object's fields, and Perl calls DESTROY when it goes out of scope.
What DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Puntuación base: 9.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- Fecha de la puntuación: 6/10/2026
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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1565Data Manipulationimpact80 %
AV:N/PR:N/UI:N permite explotación remota sin privilegios (T1190). El tag YAML malicioso ejecuta métodos DESTROY arbitrarios causando manipulación de datos o ejecución de código vía File::Temp::Dir.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-470, CWE-502
Referencias
- https://github.com/ingydotnet/yaml-pm/commit/471314bbdcbd62077eea32755929122aa8bd00a3.patch
- https://github.com/ingydotnet/yaml-pm/commit/7736f38bd02e4f9f77d5468721e3be3d7b34a8ec.patch
- https://github.com/ingydotnet/yaml-pm/issues/176
- https://metacpan.org/release/TINITA/YAML-1.30/changes
- http://www.openwall.com/lists/oss-security/2026/10/05/8
JSON original (NVD)
Mostrar
{
"id": "CVE-2017-20285",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2017-20285",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-10-06T17:02:52.193961Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.1,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"affectedData": [
{
"repo": "https://github.com/ingydotnet/yaml-pm",
"modules": [
"YAML"
],
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "1.30",
"versionType": "custom"
}
],
"packageURL": "pkg:cpan/YAML",
"packageName": "YAML",
"programFiles": [
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"lib/YAML/Loader.pm",
"lib/YAML/Types.pm"
],
"collectionURL": "https://cpan.org/modules",
"defaultStatus": "unaffected",
"programRoutines": [
{
"name": "YAML::Loader::_parse_explicit"
},
{
"name": "YAML::Type::code::yaml_load"
},
{
"name": "YAML::Type::regexp::yaml_load"
}
]
}
]
}
],
"published": "2026-10-05T07:16:29.017",
"references": [
{
"url": "https://github.com/ingydotnet/yaml-pm/commit/471314bbdcbd62077eea32755929122aa8bd00a3.patch",
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"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
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{
"url": "https://metacpan.org/release/TINITA/YAML-1.30/changes",
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{
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"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"description": [
{
"lang": "en",
"value": "CWE-470"
},
{
"lang": "en",
"value": "CWE-502"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes.\n\nA perl/hash:Class tag blesses a hash into the class it names. The document supplies the object's fields, and Perl calls DESTROY when it goes out of scope.\n\nWhat DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names."
}
],
"lastModified": "2026-10-06T17:17:08.657",
"sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
}