CVE-2021-40444

KEV
Published: Set 15, 2021 Last Modified: Ott 30, 2025
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,8
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: required
Scope: changed
Confidentiality: low
Integrity: high
Availability: low
MEDIUM 6,8
Access Vector: network
Access Complexity: medium
Authentication: none
Confidentiality: partial
Integrity: partial
Availability: partial

Description

AI Translation Available

<p>Microsoft is investigating reports of a remote code execution vulnerability in MSHTML that affects Microsoft Windows. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability by using specially-crafted Microsoft Office documents.</p>
<p>An attacker could craft a malicious ActiveX control to be used by a Microsoft Office document that hosts the browser rendering engine. The attacker would then have to convince the user to open the malicious document. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.</p>
<p>Microsoft Defender Antivirus and Microsoft Defender for Endpoint both provide detection and protections for the known vulnerability. Customers should keep antimalware products up to date. Customers who utilize automatic updates do not need to take additional action. Enterprise customers who manage updates should select the detection build 1.349.22.0 or newer and deploy it across their environments. Microsoft Defender for Endpoint alerts will be displayed as: “Suspicious Cpl File Execution”.</p>
<p>Upon completion of this investigation, Microsoft will take the appropriate action to help protect our customers. This may include providing a security update through our monthly release process or providing an out-of-cycle security update, depending on customer needs.</p>
<p>Please see the <strong>Mitigations</strong> and <strong>Workaround</strong> sections for important information about steps you can take to protect your system from this vulnerability.</p>
<p><strong>UPDATE</strong> September 14, 2021: Microsoft has released security updates to address this vulnerability. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. Please see the FAQ for important information about which updates are applicable to your system.</p>

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,9433
Percentile
1,0th
Updated

EPSS Score Trend (Last 91 Days)

22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Stable
Common Consequences
Security Scopes Affected:
Integrity Confidentiality Availability
Potential Impacts:
Execute Unauthorized Code Or Commands Modify Files Or Directories Read Files Or Directories Dos: Crash, Exit, Or Restart
Applicable Platforms
Technologies: AI/ML
View CWE Details
Operating System

Windows Server 2004 by Microsoft

Version Range Affected
To 10.0.19041.1237 (exclusive)
cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2022 by Microsoft

Version Range Affected
To 10.0.20348.230 (exclusive)
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1809 by Microsoft

Version Range Affected
To 10.0.17763.2183 (exclusive)
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 20H2 by Microsoft

Version Range Affected
To 10.0.19042.1237 (exclusive)
cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1607 by Microsoft

Version Range Affected
To 10.0.14393.4651 (exclusive)
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2012 by Microsoft

cpe:2.3:o:microsoft:windows_server_2012:-:r2:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2008 by Microsoft

cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 20H2 by Microsoft

Version Range Affected
To 10.0.19042.1237 (exclusive)
cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2019 by Microsoft

Version Range Affected
To 10.0.17763.2183 (exclusive)
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2012 by Microsoft

cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2008 by Microsoft

cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1507 by Microsoft

Version Range Affected
To 10.0.10240.19060 (exclusive)
cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 7 by Microsoft

cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Rt 8.1 by Microsoft

cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 21H1 by Microsoft

Version Range Affected
To 10.0.19043.1237 (exclusive)
cpe:2.3:o:microsoft:windows_10_21h1:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 8.1 by Microsoft

cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2016 by Microsoft

Version Range Affected
To 10.0.14393.4651 (exclusive)
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1909 by Microsoft

Version Range Affected
To 10.0.18363.1801 (exclusive)
cpe:2.3:o:microsoft:windows_10_1909:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 2004 by Microsoft

Version Range Affected
To 10.0.19041.1237 (exclusive)
cpe:2.3:o:microsoft:windows_10_2004:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021…
http://packetstormsecurity.com/files/164210/Microsoft-Windows-MSHTML-Overview.h…
http://packetstormsecurity.com/files/165214/Microsoft-Office-Word-MSHTML-Remote…
http://packetstormsecurity.com/files/167317/Microsoft-Office-MSDT-Follina-Proof…
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-404…
http://packetstormsecurity.com/files/164210/Microsoft-Windows-MSHTML-Overview.h…
http://packetstormsecurity.com/files/165214/Microsoft-Office-Word-MSHTML-Remote…
http://packetstormsecurity.com/files/167317/Microsoft-Office-MSDT-Follina-Proof…
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-404…