CVE-2021-28454: Microsoft Excel XLS File Parsing Use-After-Free Remote Code Execution Vulnerability

Published Apr 13, 2021
·
Updated

Microsoft Excel Remote Code Execution Vulnerability

Other sources

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Microsoft Excel. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of XLS files. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process.

ZDI

Affected Software

29 affected componentsFixes available
Microsoft Excel 2010
Microsoft Office Online Server
Microsoft Excel 2010
Microsoft Excel 2013
Microsoft Excel 2013
Microsoft Office 2013
Microsoft Office 2013
Microsoft Excel 2013 RT
Microsoft Office Web Apps Server 2013
Microsoft Office 2019 for 32-bit editions
Microsoft Excel
Microsoft Office 2019 for 64-bit editions
Microsoft Office 2016
Microsoft Office 2010
Microsoft Office 2016
Microsoft Office 2010
Microsoft 365 Apps for Enterprise
Microsoft 365 Apps for Enterprise
Microsoft 365 Apps
Microsoft Office=2010-sp2
Microsoft Office=2013-sp1
Microsoft Office=2013-sp1
Microsoft Office=2016
Microsoft Office=2019
Microsoft Office Online Server
Microsoft Office Web Apps Server=2013-sp1
Microsoft Excel 2016
Microsoft Excel 2016
Microsoft Office 2013 RT

Event History

Apr 13, 2021
CVE Published
via Microsoft·07:00 AM
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeakness
CVE Published
via MITRE·07:33 PM
Data Sourced
via MITRE·07:33 PM
DescriptionSeverity
Feb 23, 2025
Advisory Published
via ZDI·10:12 AM
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Frequently Asked Questions

1

What is CVE-2021-28454?

CVE-2021-28454 is a vulnerability that allows remote attackers to execute arbitrary code on affected installations of Microsoft Excel.

2

How can the CVE-2021-28454 vulnerability be exploited?

The CVE-2021-28454 vulnerability can be exploited by visiting a malicious page or opening a malicious file.

3

What is the severity of CVE-2021-28454?

CVE-2021-28454 has a severity rating of 7.8, which is considered high.

4

Which versions of Microsoft Excel are affected by CVE-2021-28454?

Microsoft Excel 2013, 2016, and Excel in Office 365 Apps for Enterprise are affected by CVE-2021-28454.

5

How can I fix CVE-2021-28454?

To fix CVE-2021-28454, apply the available patches and updates provided by Microsoft for the affected versions of Excel.

Contact

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