CVE-2021-31177: Microsoft Excel XLS File Parsing Use-After-Free Remote Code Execution Vulnerability
Microsoft Office 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
Remediation
Event History
Frequently Asked Questions
What is CVE-2021-31177?
CVE-2021-31177 is a vulnerability that allows remote attackers to execute arbitrary code on affected installations of Microsoft Excel.
How severe is CVE-2021-31177?
CVE-2021-31177 has a severity rating of 7.8, which is considered high.
Which software products are affected by CVE-2021-31177?
Microsoft Excel 2013, Excel 2013 RT, Office Web Apps Server 2013, Excel 2016, Excel 2013 64-bit, Microsoft Office 365 Apps for Enterprise, Microsoft Office 2019, Office 2019 for Mac, and Office Online Server are affected by CVE-2021-31177.
Is user interaction required to exploit CVE-2021-31177?
Yes, user interaction is required to exploit CVE-2021-31177. The target must visit a malicious page or open a malicious file.
How can I fix CVE-2021-31177?
To fix CVE-2021-31177, you should apply the relevant patches or updates provided by Microsoft for the affected software.