CVE-2020-28020
Estado: ModificadaCrítica (9.8)—
Exim 4 before 4.92 allows Integer Overflow to Buffer Overflow, in which an unauthenticated remote attacker can execute arbitrary code by leveraging the mishandling of continuation lines during header-length restriction.
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: 7.94%
- Percentil entre todas las CVEs puntuadas: 95
- 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).
Tecnologías afectadas (1)
CWE
- CWE-190
Referencias
- http://www.openwall.com/lists/oss-security/2021/07/25/1
- http://www.openwall.com/lists/oss-security/2021/08/03/1
- https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt
- http://www.openwall.com/lists/oss-security/2021/07/25/1
- http://www.openwall.com/lists/oss-security/2021/08/03/1
- https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt
JSON original (NVD)
Mostrar
{
"id": "CVE-2020-28020",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 7.5,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "LOW",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "PARTIAL"
},
"acInsufInfo": false,
"impactScore": 6.4,
"baseSeverity": "HIGH",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"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": "cve@mitre.org",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2021-05-06T13:15:09.613",
"references": [
{
"url": "http://www.openwall.com/lists/oss-security/2021/07/25/1",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "http://www.openwall.com/lists/oss-security/2021/08/03/1",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "http://www.openwall.com/lists/oss-security/2021/07/25/1",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://www.openwall.com/lists/oss-security/2021/08/03/1",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-190"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Exim 4 before 4.92 allows Integer Overflow to Buffer Overflow, in which an unauthenticated remote attacker can execute arbitrary code by leveraging the mishandling of continuation lines during header-length restriction."
},
{
"lang": "es",
"value": "Exim 4 versiones anteriores a 4.92, permite un Desbordamiento de Enteros para un Desbordamiento de Búfer, en el que un atacante remoto no autenticado pueda ejecutar código arbitrario aprovechando el manejo inapropiado de líneas de continuación durante la restricción de la longitud del encabezado"
}
],
"lastModified": "2026-06-17T03:10:00.880",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "0DE7BE8D-3B6E-4EAC-9C21-5F44A5B5ACEA",
"versionEndExcluding": "4.92",
"versionStartIncluding": "4.00"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "cve@mitre.org"
}