CVE-2026-86326
An improper verification of cryptographic signature vulnerability exists in protocol gateways because the device does not properly verify the cryptographic authenticity of firmware images before installation. An attacker with high privileges and access to the firmware update interface could provide a specially crafted or modified firmware image, causing it to be installed on the device. Successful exploitation could allow the attacker to execute unauthorized code, compromise the integrity and availability of the device, and persist malicious modifications across subsequent firmware updates.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 8.6
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.19%
- Percentil entre todas las CVEs puntuadas: 8
- Fecha de la puntuación: 4/10/2026
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
T1210Exploitation of Remote Serviceslateral movement75 % - Impacto principal
T1553.006Code Signing Policy Modificationdefense impairment80 % - Impacto secundario
T1059Command and Scripting Interpreterexecution70 % - Impacto secundario
T1561.002Disk Structure Wipeimpact65 %
Acceso red con PR:H a interfaz de actualización firmware sin validación criptográfica (CWE-347). Permite instalar código malicioso persistente, comprometiendo integridad y disponibilidad del dispositivo.
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
CWE
- CWE-347
Referencias
JSON original (NVD)
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{
"id": "CVE-2026-86326",
"cveTags": [],
"metrics": {
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{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-86326",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-10-02T10:37:09.559538Z"
}
}
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"cvssMetricV40": [
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"type": "Secondary",
"source": "psirt@moxa.com",
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"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"exploitMaturity": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED",
"userInteraction": "NONE",
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"attackRequirements": "NONE",
"privilegesRequired": "HIGH",
"subIntegrityImpact": "NONE",
"vulnIntegrityImpact": "HIGH",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "HIGH",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "NONE",
"vulnConfidentialityImpact": "HIGH",
"confidentialityRequirement": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
}
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"affected": [
{
"source": "psirt@moxa.com",
"affectedData": [
{
"vendor": "Moxa",
"product": "MGate MB3170 Series",
"versions": [
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"version": "1.0"
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{
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"published": "2026-10-02T11:17:36.330",
"references": [
{
"url": "https://www.moxa.com/en/support/product-support/security-advisory/mpsa-269540-cve-2026-86325,-cve-2026-86326-two-vulnerabilities-in-protocol-gateways",
"source": "psirt@moxa.com"
}
],
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
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"type": "Secondary",
"source": "psirt@moxa.com",
"description": [
{
"lang": "en",
"value": "CWE-347"
}
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}
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"descriptions": [
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"value": "An improper verification of cryptographic signature vulnerability exists in protocol gateways because the device does not properly verify the cryptographic authenticity of firmware images before installation. An attacker with high privileges and access to the firmware update interface could provide a specially crafted or modified firmware image, causing it to be installed on the device. Successful exploitation could allow the attacker to execute unauthorized code, compromise the integrity and availability of the device, and persist malicious modifications across subsequent firmware updates."
}
],
"lastModified": "2026-10-02T19:10:09.143",
"sourceIdentifier": "psirt@moxa.com"
}