CVE-2021-29974
Estado: ModificadaMedia (4.3)—
Cuando se habilitaba la partición de la red, por ejemplo, como resultado de la configuración de la Protección de Seguimiento Mejorada, una página de error TLS permitía al usuario anular un error en un dominio que había especificado Seguridad de Transporte Estricta HTTP (que implica que el error no debería poder anularse). Esta vulnerabilidad afecta a Firefox versiones anteriores a 90
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
- Puntuación base: 4.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.84%
- Percentil entre todas las CVEs puntuadas: 57
- Fecha de la puntuación: 9/10/2026
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
- NVD-CWE-noinfo
Referencias
- https://bugzilla.mozilla.org/show_bug.cgi?id=1704843
- https://security.gentoo.org/glsa/202202-03
- https://www.mozilla.org/security/advisories/mfsa2021-28/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1704843
- https://security.gentoo.org/glsa/202202-03
- https://www.mozilla.org/security/advisories/mfsa2021-28/
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-29974",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 2.6,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:H/Au:N/C:N/I:P/A:N",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "HIGH",
"availabilityImpact": "NONE",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "LOW",
"obtainAllPrivilege": false,
"exploitabilityScore": 4.9,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": true
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 4.3,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 1.4,
"exploitabilityScore": 2.8
}
]
},
"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"status": "affected",
"version": "unspecified",
"lessThan": "90",
"versionType": "custom"
}
]
}
]
}
],
"published": "2021-08-05T20:15:08.697",
"references": [
{
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1704843",
"tags": [
"Issue Tracking",
"Vendor Advisory"
],
"source": "security@mozilla.org"
},
{
"url": "https://security.gentoo.org/glsa/202202-03",
"tags": [
"Third Party Advisory"
],
"source": "security@mozilla.org"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2021-28/",
"tags": [
"Vendor Advisory"
],
"source": "security@mozilla.org"
},
{
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1704843",
"tags": [
"Issue Tracking",
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://security.gentoo.org/glsa/202202-03",
"tags": [
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2021-28/",
"tags": [
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "When network partitioning was enabled, e.g. as a result of Enhanced Tracking Protection settings, a TLS error page would allow the user to override an error on a domain which had specified HTTP Strict Transport Security (which implies that the error should not be override-able.) This issue did not affect the network connections, and they were correctly upgraded to HTTPS automatically. This vulnerability affects Firefox < 90."
},
{
"lang": "es",
"value": "Cuando se habilitaba la partición de la red, por ejemplo, como resultado de la configuración de la Protección de Seguimiento Mejorada, una página de error TLS permitía al usuario anular un error en un dominio que había especificado Seguridad de Transporte Estricta HTTP (que implica que el error no debería poder anularse). Esta vulnerabilidad afecta a Firefox versiones anteriores a 90"
}
],
"lastModified": "2026-06-17T03:48:32.310",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "FA0BA5A6-A40E-418E-A536-9A14711264B7",
"versionEndExcluding": "90.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security@mozilla.org"
}