CVE-2021-43905
published 2021-12-15CVE-2021-43905: Microsoft Office app Remote Code Execution Vulnerability
PriorityP355critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
EPSS
2.82%
85.0th percentile
Microsoft Office app Remote Code Execution Vulnerability
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | 365_copilot | < 18.2110.13110.0 | 18.2110.13110.0 |
| microsoft | office_app | < publication | publication |
| msrc | office_app | — | — |
CVSS provenance
nvdv3.19.6CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
vendor_msrc9.6CRITICAL
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Microsoft
Microsoft Office app Remote Code Execution Vulnerability
vendor_msrc·2021-12-14·CVSS 9.6
CVE-2021-43905 [CRITICAL] Microsoft Office app Remote Code Execution Vulnerability
Microsoft Office app Remote Code Execution Vulnerability
FAQ: How do I get the update for Office app?
The Microsoft Store will automatically update affected customers. Alternatively, customers can get the update immediately; see here for details. Be sure to select the tab for the operating system installed on your device to search for updates.
It is possible for customers to disable automatic updates for the Microsoft Store. The Microsoft Store will not automatically install this update for those customers. You can get the update through the store here: ms-windows-store://pdp/?productid=9WZDNCRD29V9.
How can I check if the update is installed?
App versions 18.2110.13110.0 and later contain this update.
FAQ: Is the Preview Pane an attack vector for this vulnerability?
No, the Preview Pane
GHSA
GHSA-p5c8-x5qh-v2mv: Microsoft Office app Remote Code Execution Vulnerability
ghsa_unreviewed·2021-12-16
CVE-2021-43905 [CRITICAL] GHSA-p5c8-x5qh-v2mv: Microsoft Office app Remote Code Execution Vulnerability
Microsoft Office app Remote Code Execution Vulnerability
No detection rules found.
No public exploits indexed.
Qualys
Steps to TruRisk™ – 2: Measure the Likelihood of Vulnerability Exploitation | Qualys
blogs_qualys·2025-04-07
Steps to TruRisk™ – 2: Measure the Likelihood of Vulnerability Exploitation | Qualys
#### Table of Contents
- Victory Belongs to the Well-Informed
- Defining the Components of Likelihood of Exploit
- The Role of CVSS, EPSS, and CISA KEV in Risk Assessment
- The Case for Context: Why Meaningful Remediation is Critical
- Qualys Vulnerability Score (QVS): A Unified Measure of Exploitability
- Qualys Detection Score (QDS): Operationalizing Risk
- Practical Evaluation of QDS vs CVSS
- From Overload to Actionable Insights
Cybersecurity programs rely on various methods to measure the risk associated with vulnerabilities for prioritization, such as CVSS, EPSS, CISA KEV, or even internally developed systems that combine multiple approaches. While these methods help assess whether a specific vulnerability exists on an asset and define its severity, traditional frameworks like CVSS
Qualys
Steps to TruRisk™ – 2: Measure the Likelihood of Vulnerability Exploitation
blogs_qualys·2025-04-07
Steps to TruRisk™ – 2: Measure the Likelihood of Vulnerability Exploitation
## Table of Contents
Victory Belongs to the Well-Informed
Defining the Components of Likelihood of Exploit
The Role of CVSS, EPSS, and CISA KEV in Risk Assessment
The Case for Context: Why Meaningful Remediation is Critical
Qualys Vulnerability Score (QVS): A Unified Measure of Exploitability
Qualys Detection Score (QDS): Operationalizing Risk
Practical Evaluation of QDS vs CVSS
From Overload to Actionable Insights
Cybersecurity programs rely on various methods to measure the risk associated with vulnerabilities for prioritization, such as CVSS, EPSS, CISA KEV, or even internally developed systems that combine multiple approaches. While these methods help assess whether a specific vulnerability exists on an asset and define its severity, traditional frameworks like CVSS often over
Qualys
Microsoft & Adobe Patch Tuesday (December 2021) – Microsoft 83 Vulnerabilities With 7 Critical, 1 Actively Exploited. Adobe 60 Vulnerabilities, 28 Critical.
blogs_qualys·2021-12-14·CVSS 9.8
[CRITICAL] Microsoft & Adobe Patch Tuesday (December 2021) – Microsoft 83 Vulnerabilities With 7 Critical, 1 Actively Exploited. Adobe 60 Vulnerabilities, 28 Critical.
## Table of Contents
Microsoft Patch Tuesday December 2021
Microsoft Vulnerabilities To Be Prioritized and Patched Quickly.
Adobe Patch Tuesday December 2021
Discover and Prioritize Patch Tuesday Vulnerabilities in VMDR
Respond by Patching
Patch Tuesday Dashboard
Webinar Series: This Month in Vulnerabilities and Patches
About Patch Tuesday
Contributor
## Microsoft Patch Tuesday – December 2021
Microsoft patched 83 vulnerabilities in their December 2021 Patch Tuesday release, of which seven are rated as critical severity. This month’s release includes one Zero Day known to be actively exploited.
Products impacted by Microsoft’s December security update include Microsoft Office, Microsoft PowerShell, the Chromium-based Edge browser, the Windows Kernel, Print Spooler, and Remote D
Krebs
Microsoft Patch Tuesday, December 2021 Edition
blogs_krebs·2021-12-14
Microsoft Patch Tuesday, December 2021 Edition
Microsoft, Adobe, and Google all issued security updates to their products today. The Microsoft patches include six previously disclosed security flaws, and one that is already being actively exploited. But this month’s Patch Tuesday is overshadowed by the “Log4Shell” 0-day exploit in a popular Java library that web server administrators are now racing to find and patch amid widespread exploitation of the flaw.
Log4Shell is the name picked for a critical flaw disclosed Dec. 9 in the popular logging library for Java called “log4j,” which is included in a huge number of Java applications. Publicly released exploit code allows an attacker to force a server running a vulnerable log4j library to execute commands, such as downloading malicious software or opening a backdoor connection to the se
Krebs
Microsoft Patch Tuesday, December 2021 Edition
blogs_krebs·2021-12-14
Microsoft Patch Tuesday, December 2021 Edition
Microsoft , Adobe , and Google all issued security updates to their products today. The Microsoft patches include six previously disclosed security flaws, and one that is already being actively exploited. But this month’s Patch Tuesday is overshadowed by the “ Log4Shell ” 0-day exploit in a popular Java library that web server administrators are now racing to find and patch amid widespread exploitation of the flaw.
Log4Shell is the name picked for a critical flaw disclosed Dec. 9 in the popular logging library for Java called “ log4j ,” which is included in a huge number of Java applications. Publicly released exploit code allows an attacker to force a server running a vulnerable log4j library to execute commands, such as downloading malicious software or opening a backdoor connection to
Tenable
Microsoft’s December 2021 Patch Tuesday Addresses 67 CVEs (CVE-2021-43890)
blogs_tenable·2021-12-14·CVSS 7.1
[HIGH] Microsoft’s December 2021 Patch Tuesday Addresses 67 CVEs (CVE-2021-43890)
## Cloud Exposure
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## Vulnerability Exposure
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## AI Exposure
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## OT/IoT Exposure
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## Identity Exposure
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## Business needs
Active Directory
AI Security Posture Management (AI-SPM)
AWS security
Azure security
Cloud Security Posture Man
Qualys
Microsoft & Adobe Patch Tuesday (December 2021) – Microsoft 83 Vulnerabilities With 7 Critical, 1 Actively Exploited. Adobe 60 Vulnerabilities, 28 Critical. | Qualys
blogs_qualys·2021-12-14·CVSS 9.8
[CRITICAL] Microsoft & Adobe Patch Tuesday (December 2021) – Microsoft 83 Vulnerabilities With 7 Critical, 1 Actively Exploited. Adobe 60 Vulnerabilities, 28 Critical. | Qualys
#### Table of Contents
- Microsoft Patch Tuesday December 2021
- Microsoft Vulnerabilities To Be Prioritized and Patched Quickly.
- Adobe Patch Tuesday December 2021
- Discover and Prioritize Patch Tuesday Vulnerabilities in VMDR
- Respond by Patching
- Patch Tuesday Dashboard
- Webinar Series: This Month in Vulnerabilities and Patches
- About Patch Tuesday
- Contributor
## Microsoft Patch Tuesday – December 2021
Microsoft patched 83 vulnerabilities in their December 2021 Patch Tuesday release, of which seven are rated as critical severity. This month’s release includes one Zero Day known to be actively exploited.
Products impacted by Microsoft’s December security update include Microsoft Office, Microsoft PowerShell, the Chromium-based Edge browser, the Windows Kernel, Print Spooler,
Crowdstrike
December 2021 Patch Tuesday: Updates and Analysis
blogs_crowdstrike·CVSS 7.5
CVE-2026-20929 [HIGH] December 2021 Patch Tuesday: Updates and Analysis
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2021-12-15
Published