CVE-2021-24020
Estado: ModificadaCrítica (9.8)—
A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.
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: 0.62%
- Percentil entre todas las CVEs puntuadas: 48
- 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-347
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-24020",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-24020",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2024-10-23T14:13:45.573210Z"
}
}
],
"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": "Secondary",
"source": "psirt@fortinet.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.6
},
{
"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": "psirt@fortinet.com",
"affectedData": [
{
"vendor": "Fortinet",
"product": "Fortinet FortiMail",
"versions": [
{
"status": "affected",
"version": "FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7"
}
]
}
]
}
],
"published": "2021-07-09T19:15:08.197",
"references": [
{
"url": "https://fortiguard.com/advisory/FG-IR-21-027",
"tags": [
"Vendor Advisory"
],
"source": "psirt@fortinet.com"
},
{
"url": "https://fortiguard.com/advisory/FG-IR-21-027",
"tags": [
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-347"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification."
},
{
"lang": "es",
"value": "Una falta de paso criptográfico en la implementación del algoritmo hash digest en FortiMail versiones 6.4.0 hasta 6.4.4, y versiones 6.2.0 hasta 6.2.7, puede permitir a un atacante no autenticado manipular las URLs firmadas al añadir más datos que permitan omitir la comprobación de la firma"
}
],
"lastModified": "2026-06-17T03:39:10.277",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:fortinet:fortimail:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "72F6AEF1-C5BF-4A9A-A843-A152AA168085",
"versionEndIncluding": "6.2.7",
"versionStartIncluding": "6.2.0"
},
{
"criteria": "cpe:2.3:a:fortinet:fortimail:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "5DAB4EFB-D73F-4FC5-8FE7-278BADB9F78E",
"versionEndExcluding": "6.4.5",
"versionStartIncluding": "6.4.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "psirt@fortinet.com"
}