CVE-2026-55133

Heap-based buffer overflow in Microsoft Office OneNote 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-2026-55133	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_2021:-::::ltsc:macos:-:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:macos:-:

History

16 Jul 2026, 16:07

Type	Values Removed	Values Added
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55133 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55133 - Vendor Advisory
CPE		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_2021:-::::ltsc:macos:-: cpe:2.3:a:microsoft:office_2024:-::::ltsc:macos:-:
First Time		Microsoft office 2024 Microsoft 365 Apps Microsoft microsoft 365 Microsoft Microsoft office 2021

14 Jul 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-14 18:18

Updated : 2026-07-22 05:17

NVD link : CVE-2026-55133

Mitre link : CVE-2026-55133

CVE.ORG link : CVE-2026-55133

JSON object : View

Products Affected

microsoft

office_2024
365_apps
office_2021
microsoft_365

CWE

CWE-122

Heap-based Buffer Overflow

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