CVE-2021-21806
Estado: ModificadaAlta (8.8)—
An exploitable use-after-free vulnerability exists in WebKitGTK browser version 2.30.3 x64. A specially crafted HTML web page can cause a use-after-free condition, resulting in remote code execution. The victim needs to visit a malicious web site to trigger the vulnerability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 2.83%
- Percentil entre todas las CVEs puntuadas: 86
- 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-416
Referencias
JSON original (NVD)
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"id": "CVE-2021-21806",
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"vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
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"published": "2021-07-08T12:15:10.013",
"references": [
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"url": "http://www.openwall.com/lists/oss-security/2021/07/23/1",
"tags": [
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{
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"vulnStatus": "Modified",
"weaknesses": [
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"description": [
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"value": "An exploitable use-after-free vulnerability exists in WebKitGTK browser version 2.30.3 x64. A specially crafted HTML web page can cause a use-after-free condition, resulting in remote code execution. The victim needs to visit a malicious web site to trigger the vulnerability."
},
{
"lang": "es",
"value": "Se presenta una vulnerabilidad explotable de uso de la memoria previamente liberada en el navegador WebKitGTK versión 2.30.3 x64. Una página web HTML especialmente diseñada puede causar una condición de uso de memoria previamente liberada, resultando en una ejecución de código remota. La víctima necesita visitar un sitio web malicioso para desencadenar la vulnerabilidad"
}
],
"lastModified": "2026-06-17T03:36:09.143",
"configurations": [
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