CVE-2021-31178: Microsoft Office Information Disclosure Vulnerability

Overview

Severity

Medium (CVSS 5.5)

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Category

Information Disclosure

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2021-May

Released

2021-05-11

EPSS Score

41.85% (percentile: 97.4%)

FAQ

What type of information could be disclosed by this vulnerability? The type of information that could be disclosed if an attacker successfully exploited this vulnerability is uninitialized memory. Is the Preview Pane an attack vector for this vulnerability? No, the Preview Pane is not an attack vector.

Affected Products (16)

Microsoft Office

• Microsoft Office 2019 for 32-bit editions
• Microsoft Office 2019 for 64-bit editions
• Microsoft Office Online Server
• Microsoft 365 Apps for Enterprise for 32-bit Systems
• Microsoft 365 Apps for Enterprise for 64-bit Systems
• Microsoft Excel 2016 (32-bit edition)
• Microsoft Excel 2016 (64-bit edition)
• Microsoft Office 2016 (32-bit edition)
• Microsoft Office 2016 (64-bit edition)
• Microsoft Excel 2013 RT Service Pack 1
• Microsoft Excel 2013 Service Pack 1 (32-bit editions)
• Microsoft Excel 2013 Service Pack 1 (64-bit editions)
• Microsoft Office 2013 RT Service Pack 1
• Microsoft Office 2013 Service Pack 1 (32-bit editions)
• Microsoft Office 2013 Service Pack 1 (64-bit editions)
• Microsoft Office Web Apps Server 2013 Service Pack 1

Security Updates (10)

• 5001914
• 5001918
• 5001918
• 5001923
• 5001923
• 5001936
• 5001936
• 5001927
• 5001927
• 5001928

Acknowledgments

Sagi Tzadik and Netanel Ben-Simon, Check Point Research

Revision History

• 2021-05-11: Information published.