CVE-2026-63521

Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-63521	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: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_2024:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x86:
	cpe:2.3:a:microsoft:word:2016::::::x64:
	cpe:2.3:a:microsoft:word:2016::::::x86:

History

No history.

Information

Published : 2026-08-11 17:18

Updated : 2026-08-14 17:33

NVD link : CVE-2026-63521

Mitre link : CVE-2026-63521

CVE.ORG link : CVE-2026-63521

JSON object : View

Products Affected

microsoft

office_2024
office_2019
365_apps
office_2021
word

CWE

CWE-125

Out-of-bounds Read

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