CVE-2026-55128

Use after free in Microsoft Office Word allows an unauthorized attacker to execute code locally.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55128	Vendor Advisory Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x64:*
	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x86:*
	cpe:2.3:a:microsoft:microsoft_365:-:::::macos::
	cpe:2.3:a:microsoft:office_2019:-::::::x64:
	cpe:2.3:a:microsoft:office_2019:-::::::x86:
	cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x86:
	cpe:2.3:a:microsoft:office_2021:-::::ltsc:macos:-:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x86:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:macos:-:
	cpe:2.3:a:microsoft:office_online_server::::::::
	cpe:2.3:a:microsoft:sharepoint_server:::::subscription:::*
	cpe:2.3:a:microsoft:sharepoint_server:2016::::enterprise:::
	cpe:2.3:a:microsoft:sharepoint_server:2019:::::::*
	cpe:2.3:a:microsoft:word:2016::::::x64:
	cpe:2.3:a:microsoft:word:2016::::::x86:

History

No history.

Information

Published : 2026-07-14 18:18

Updated : 2026-07-16 14:32

NVD link : CVE-2026-55128

Mitre link : CVE-2026-55128

CVE.ORG link : CVE-2026-55128

JSON object : View

Products Affected

microsoft

office_2024
office_2019
microsoft_365
365_apps
sharepoint_server
office_2021
office_online_server
word

CWE

CWE-416

Use After Free

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"version": "16.0.1", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Office 2019", "versions": [{"status": "affected", "version": "19.0.0", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Office 365 for Mac", "versions": [{"status": "affected", "version": "1.0.0", "lessThan": "16.111.26071215", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC 2021", "versions": [{"status": "affected", "version": "16.0.1", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC 2024", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC for Mac 2021", "versions": [{"status": "affected", "version": "16.0.1", "lessThan": "16.111.26071215", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC for Mac 2024", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.111.26071215", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft SharePoint Enterprise Server 2016", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.0.5561.1001", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft SharePoint Server 2019", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.0.10417.20175", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft SharePoint Server Subscription Edition", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.0.19725.20434", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Word 2016", "versions": [{"status": "affected", "version": "16.0.1", "lessThan": "16.0.5561.1000", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}]}], "published": "2026-07-14T18:18:19.320", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55128", "tags": ["Vendor Advisory", "Patch"], "source": "secure@microsoft.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "Use after free in Microsoft Office Word allows an unauthorized attacker to execute code locally."}], "lastModified": "2026-07-16T14:32:46.910", "configurations": 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