CVE-2026-40358
Full vulnerability record from the local CVENow database.
Description
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
Severity
HIGH
CVSS score
8.4
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-05-12 18:17:14.543000
Last modified
2026-10-26 18:10:00.173000
View original CVE JSON
{
"id": "CVE-2026-40358",
"sourceIdentifier": "[email protected]",
"published": "2026-05-12T18:17:14.543",
"lastModified": "2026-10-26T18:10:00.173",
"vulnStatus": "Modified",
"cveTags": [],
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{
"lang": "en",
"value": "Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally."
},
{
"lang": "es",
"value": "Desbordamiento de búfer basado en montículo en Microsoft Office permite a un atacante no autorizado ejecutar código localmente."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Microsoft",
"product": "Microsoft 365 Apps for Enterprise",
"platforms": [
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"x64-based Systems"
],
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{
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"lessThan": "https://aka.ms/OfficeSecurityReleases",
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"status": "affected"
}
]
},
{
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],
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{
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}
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},
{
"vendor": "Microsoft",
"product": "Microsoft Office 2019",
"platforms": [
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],
"versions": [
{
"version": "19.0.0",
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},
{
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],
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},
{
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"product": "Microsoft Office LTSC 2024",
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],
"metrics": {
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{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 8.4,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
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"impactScore": 5.9
}
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"ssvcV203": [
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"ssvcData": {
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"id": "CVE-2026-40358",
"options": [
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{
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{
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],
"role": "CISA Coordinator",
"version": "2.0.3"
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-416"
}
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"references": [
{
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40358",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
}
]
}