Untrusted Pointer Dereference in Microsoft Office Excel by Microsoft
CVE-2026-20955

7.8HIGH

Key Information:

Vendor

Microsoft
Status
Office Online Server
Microsoft Office 2019
Microsoft 365 Apps For Enterprise
Microsoft Office Ltsc For Mac 2021
Vendor
CVE Published:
13 January 2026

What is CVE-2026-20955?

The vulnerability in Microsoft Office Excel arises from an untrusted pointer dereference issue, which can allow unauthorized users to execute code on affected systems. This flaw poses a significant risk, potentially enabling malware execution through specially crafted documents. Users are encouraged to apply recommended security patches promptly to mitigate this vulnerability.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Office 2019 32-bit Systems 19.0.0

Microsoft Office LTSC 2021 x64-based Systems 16.0.1

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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