Use-After-Free in Microsoft Excel Enables Local Code Execution

Publication date: 2026-01-13

Last updated on: 2026-01-13

Assigner: Microsoft Corporation

Description

Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-01-13

Last Modified

2026-01-13

Generated

2026-07-06

AI Q&A

2026-01-14

EPSS Evaluated

2026-07-05

NVD

CVE-2026-20950

Affected Vendors & Products

Vendor	Product	Version / Range
microsoft	office_excel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-416	The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Attack-Flow Graph

Executive Summary

This vulnerability is a use-after-free issue in Microsoft Office Excel that allows an unauthorized attacker to execute code locally on the affected system.

Impact Analysis

An attacker could exploit this vulnerability to run malicious code on your system with the privileges of the user running Excel, potentially leading to data loss, system compromise, or further attacks.

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