CVE-2026-109588
Full vulnerability record from the local CVENow database.
Description
Numeric truncation of the buffer length in the MPU buffer authorization check in FreeRTOS-Kernel V11.3.0 and V11.3.1 on the Arm Cortex-R82 (Armv8-R AArch64) MPU port might allow, under certain conditions, an unprivileged task on MPU-enabled builds to read or write privileged kernel memory beyond the validated buffer window, via a stream buffer system call. To remediate this issue, users should upgrade to version V11.3.2 or later.
Severity
CRITICAL
CVSS score
9.3
(v4.0)
Vulnerability status
Awaiting Analysis
Source identifier
ff89ba41-3aa1-4d27-914a-91399e9639e5
Published
2026-10-16 18:17:31.457000
Last modified
2026-10-20 19:17:28.967000
View original CVE JSON
{
"id": "CVE-2026-109588",
"sourceIdentifier": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"published": "2026-10-16T18:17:31.457",
"lastModified": "2026-10-20T19:17:28.967",
"vulnStatus": "Awaiting Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Numeric truncation of the buffer length in the MPU buffer authorization check in FreeRTOS-Kernel V11.3.0 and V11.3.1 on the Arm Cortex-R82 (Armv8-R AArch64) MPU port might allow, under certain conditions, an unprivileged task on MPU-enabled builds to read or write privileged kernel memory beyond the validated buffer window, via a stream buffer system call.\n\n\n\nTo remediate this issue, users should upgrade to version V11.3.2 or later."
}
],
"affected": [
{
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"affectedData": [
{
"vendor": "FreeRTOS",
"product": "FreeRTOS-Kernel",
"defaultStatus": "unaffected",
"versions": [
{
"version": "11.3.0",
"lessThanOrEqual": "11.3.1",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/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",
"baseScore": 9.3,
"baseSeverity": "CRITICAL",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"subAvailabilityImpact": "HIGH",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"cvssMetricV31": [
{
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.0,
"impactScore": 6.0
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-20T17:30:55.749548Z",
"id": "CVE-2026-109588",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-125"
},
{
"lang": "en",
"value": "CWE-197"
},
{
"lang": "en",
"value": "CWE-787"
}
]
}
],
"references": [
{
"url": "https://aws.amazon.com/security/security-bulletins/2026-138-aws/",
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
},
{
"url": "https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V11.3.2",
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
},
{
"url": "https://github.com/FreeRTOS/FreeRTOS-Kernel/security/advisories/GHSA-qf4j-6f5j-876g",
"source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
}
]
}