CVE-2026-78997
UC Browser for Android (package com.UCMobile.intl, version 13.7.8.1314) contains a Universal Cross-Site Scripting vulnerability that allows an attacker to execute arbitrary JavaScript in the context of any origin. An attacker hosts a specially crafted URL on a UC-owned domain (via a reflected XSS) that leverages the browser's internal JavaScript bridge to register a deferred callback, navigate the tab to a victim site, and then execute attacker-controlled code on that site when a login dialog is dismissed.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
- Puntuación base: 9.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.40%
- Percentil entre todas las CVEs puntuadas: 32
- Fecha de la puntuación: 5/10/2026
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
T1189Drive-by Compromiseinitial access95 % - Impacto principal
T1059.007JavaScriptexecution90 % - Impacto secundario
T1005Data from Local Systemcollection75 %
XSS reflejado en dominio UC Browser (CWE-79, CVSS UI:R) ejecuta JavaScript arbitrario en contexto de cualquier origen. Acceso a datos del sitio víctima incluido.
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-79
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-78997",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-78997",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-09-09T18:15:20.006490Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 9.3,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.8,
"exploitabilityScore": 2.8
}
]
},
"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2026-09-08T17:18:31.020",
"references": [
{
"url": "https://gist.github.com/OmriInbar-Novee/9fd65fe08c1b1cff6a19350e44425de2",
"source": "cve@mitre.org"
},
{
"url": "https://gist.github.com/OmriInbar-Novee/ef7a92db148b2eb1ab0aa7b99a565c4c",
"source": "cve@mitre.org"
},
{
"url": "https://gist.github.com/OmriInbar-Novee/9fd65fe08c1b1cff6a19350e44425de2",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"description": [
{
"lang": "en",
"value": "CWE-79"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "UC Browser for Android (package com.UCMobile.intl, version 13.7.8.1314) contains a Universal Cross-Site Scripting vulnerability that allows an attacker to execute arbitrary JavaScript in the context of any origin. An attacker hosts a specially crafted URL on a UC-owned domain (via a reflected XSS) that leverages the browser's internal JavaScript bridge to register a deferred callback, navigate the tab to a victim site, and then execute attacker-controlled code on that site when a login dialog is dismissed."
}
],
"lastModified": "2026-09-09T19:17:47.723",
"sourceIdentifier": "cve@mitre.org"
}