CVE-2026-5818
Incorrect check of function return value in Caliptra Core Runtime Firmware (ActivateFirmwareCmd::activate_fw modules) allows bypass of Caliptra Core's verification of the MCU FW during a hitless update.
This issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:H/SC:H/SI:H/SA:H/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: 7.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.24%
- Percentil entre todas las CVEs puntuadas: 14
- 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).
🎯 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
T1565.001Stored Data Manipulationimpact70 % - Impacto secundario
T1068Exploitation for Privilege Escalationprivilege escalation65 %
AV:A + PR:H permite red adyacente con privilegios elevados (T1210). VI:H/VA:H + CWE-253 (fallo de validación) permite modificar firmware MCU sin verificación, afectando integridad (T1565.001) y escalada (T1068).
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-253
Referencias
JSON original (NVD)
Mostrar
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"role": "CISA Coordinator",
"options": [
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{
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{
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"version": "2.0.3",
"timestamp": "2026-06-24T13:04:30.529915Z"
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"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:A/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:H/SC:H/SI:H/SA:H/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",
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"vulnerabilityResponseEffort": "NOT_DEFINED",
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"modifiedSubConfidentialityImpact": "NOT_DEFINED",
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"affected": [
{
"source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554",
"affectedData": [
{
"vendor": "Caliptra",
"modules": [
"ActivateFirmwareCmd::activate_fw"
],
"product": "Core Runtime Firmware",
"versions": [
{
"status": "affected",
"version": "2.0.0",
"versionType": "semver",
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{
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{
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"version": "2.0.2",
"versionType": "semver"
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{
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"version": "2.1.1",
"versionType": "semver"
}
],
"packageName": "Core Runtime Firmware",
"collectionURL": "https://github.com/chipsalliance/caliptra-sw",
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-06-24T00:16:33.830",
"references": [
{
"url": "https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-456r-gcjr-6rxq",
"source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554"
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"source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554",
"description": [
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"value": "Incorrect check of function return value in Caliptra Core Runtime Firmware (ActivateFirmwareCmd::activate_fw modules) allows bypass of Caliptra Core's verification of the MCU FW during a hitless update.\n\nThis issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0."
}
],
"lastModified": "2026-06-25T16:14:14.483",
"sourceIdentifier": "b01ddd03-5ef6-483b-b2c5-acba77f1a554"
}