Important CVSS 5.5 EPSS 0.04352 2020-09 archive

Executive Summary

An information disclosure vulnerability exists when Microsoft Excel improperly discloses the contents of its memory. An attacker who exploited the vulnerability could use the information to compromise the user’s computer or data. To exploit the vulnerability, an attacker could craft a special document file and then convince the user to open it. An attacker must know the memory address location where the object was created. The update addresses the vulnerability by changing the way certain Excel functions handle objects in memory.

Overview

5.5
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Information Disclosure
Released Sep 8 2020
Last Updated Sep 8 2020
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.04352 — 0.89969 percentile
NVD CVSS 5.5 MEDIUM — matches MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C
ATTACK VECTOR
Local
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
Required
SCOPE
Unchanged
CONFIDENTIALITY
High
INTEGRITY
None
AVAILABILITY
None
EXPLOIT CODE MATURITY
Proof-of-Concept
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 5.0

EPSS Score

0.04352
probability of exploitation in the next 30 days
0.89969 percentile - updated 2026-06-21
View on FIRST.org

Affected Products

16 affected products
Product KB Article Severity Impact Restart Required
Microsoft 365 Apps for Enterprise for 32-bit Systems Click to Run (Security Update) Important Information Disclosure No
Microsoft 365 Apps for Enterprise for 64-bit Systems Click to Run (Security Update) Important Information Disclosure No
Microsoft Excel 2010 Service Pack 2 (32-bit editions) 4486665 (Security Update) Important Information Disclosure Maybe
Microsoft Excel 2010 Service Pack 2 (64-bit editions) 4486665 (Security Update) Important Information Disclosure Maybe
Microsoft Excel 2013 RT Service Pack 1 4484526 (Security Update) Important Information Disclosure Maybe
Microsoft Excel 2013 Service Pack 1 (32-bit editions) 4484526 (Security Update) Important Information Disclosure Maybe
Microsoft Excel 2013 Service Pack 1 (64-bit editions) 4484526 (Security Update) Important Information Disclosure Maybe
Microsoft Excel 2016 (32-bit edition) 4484507 (Security Update) Important Information Disclosure Maybe
Microsoft Excel 2016 (64-bit edition) 4484507 (Security Update) Important Information Disclosure Maybe
Microsoft Office 2016 for Mac Release Notes (Security Update) Important Information Disclosure No
Microsoft Office 2019 for 32-bit editions Click to Run (Security Update) Important Information Disclosure No
Microsoft Office 2019 for 64-bit editions Click to Run (Security Update) Important Information Disclosure No
Microsoft Office 2019 for Mac Release Notes (Security Update) Important Information Disclosure No
Microsoft Office Online Server 4484503 (Security Update) Important Information Disclosure Maybe
Microsoft Office Web Apps 2013 Service Pack 1 4484518 (Security Update) Important Information Disclosure Maybe
Microsoft SharePoint Enterprise Server 2013 Service Pack 1 4484516 (Security Update) Important Information Disclosure Maybe

Patches

8 patches
Article Type Restart
Click to Run Security Update No
4486665 Security Update Maybe
4484526 Security Update Maybe
4484507 Security Update Maybe
Release Notes Security Update No
4484503 Security Update Maybe
4484518 Security Update Maybe
4484516 Security Update Maybe

Known Exploits

Acknowledgments

Jinquan(@jq0904) of DBAPPSecurity Co., Ltd