CVE-2026-21511

Deserialization of untrusted data in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21511	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_long_term_servicing_channel:2021:::::-:x64:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:::::-:x86:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:::::macos::
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:::::-:x64:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:::::-:x86:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:::::macos::
	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 : 2026-02-10 18:16

Updated : 2026-02-11 18:56

NVD link : CVE-2026-21511

Mitre link : CVE-2026-21511

CVE.ORG link : CVE-2026-21511

JSON object : View

Products Affected

microsoft

word
office
office_long_term_servicing_channel
sharepoint_server
365_apps

CWE

CWE-502

Deserialization of Untrusted Data

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