CVE-2026-64909

Integer underflow (wrap or wraparound) in Microsoft Office 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-2026-64909	Patch Vendor Advisory

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_2016:-::::-::x64:*
	cpe:2.3:a:microsoft:office_2016:-::::-::x86:*
	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:-:

History

No history.

Information

Published : 2026-08-11 17:18

Updated : 2026-08-14 17:47

NVD link : CVE-2026-64909

Mitre link : CVE-2026-64909

CVE.ORG link : CVE-2026-64909

JSON object : View

Products Affected

microsoft

office_2024
office_2016
office_2019
microsoft_365
365_apps
office_2021

CWE

CWE-122

Heap-based Buffer Overflow

CWE-125

Out-of-bounds Read

CWE-191

Integer Underflow (Wrap or Wraparound)

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