Overview
On February 12, NSFOCUS CERT detected that Microsoft released a security update patch for February, which fixed 63 security issues involving widely used products such as Windows, Microsoft Office, Azure, Apps, and Microsoft Visual Studio, including high-risk vulnerabilities such as privilege escalation and remote code execution.
Among the vulnerabilities fixed in Microsoft’s monthly update this month, 4 are critical and
(Important) There are 56 vulnerabilities. These included 2 detected exploits:
Windows Storage Permission Escalation Vulnerability (CVE-2025-21391)
WinSock Elevation of Privilege Vulnerability for Windows Ancillary Function Driver (CVE-2025-21418)
Please update patches for protection as soon as possible. For a complete list of vulnerabilities, see the appendix.
Reference link: https://msrc.microsoft.com/update-guide/en-us/releaseNote/2025-Feb
Key Vulnerabilities
Screen out the vulnerabilities with great impact in this update according to product popularity and vulnerability importance. Please pay attention to them:
WinSock Elevation of Privilege Vulnerability of Windows Accessibility Driver (CVE-2025-21418):
A elevation of privilege vulnerability exists in WinSock of the Windows helper driver, where an authenticated local attacker can trigger a heap buffer overflow to gain SYSTEM privileges for the system due to boundary errors in the Winsock’s helper driver. The vulnerability has been exploited, with a CVSS score of 7.8.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21418
Windows Storage Permission Escalation Vulnerability (CVE-2025-21391):
A elevation of privilege vulnerability is present in the Windows storage where a local attacker can execute code with SYSTEM privileges on the target system to delete arbitrary files due to improper link parsing in the Windows storage. The vulnerability has been exploited, with a CVSS score of 7.1.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21391
Windows Lightweight Directory Access Protocol (LDAP) Remote Code Execution Vulnerability (CVE-2025-21376):
Windows LDAP has a remote code execution vulnerability. An unauthenticated attacker can cause buffer overflow and execute arbitrary code on the target system after winning the competition condition by sending a special LDAP request. The CVSS score was 8.1.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21376
Microsoft Excel Remote Code Execution Vulnerability (CVE-2025-21381):
Microsoft Excel has a remote code execution vulnerability. Due to unreliable pointer de-reference in Microsoft Excel, remote attackers can execute arbitrary code on the target system by coaxing the victim to open a special excel file. The CVSS score was 7.8.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21381
DHCP Client Service Remote Code Execution Vulnerability (CVE-2025-21379):
The DHCP client service has a remote code execution vulnerability. Due to the reuse after release in the DHCP client service, attackers in the local network can launch man-in-the-middle attacks and execute codes with SYSTEM privileges on the target system. The CVSS score was 7.1.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21379
NTLM Hash Leak Spoofing Vulnerability (CVE-2025-21377):
NTLM has a hash leak spoofing vulnerability. An attacker can obtain the NTLMV2 hash by tricking a user to click on a special link, and then log in to the system as the user. The vulnerability has been publicly disclosed with a CVSS score of 6.5.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21377
Microsoft SharePoint Server Remote Code Execution Vulnerability (CVE-2025-21400):
Microsoft SharePoint Server has a remote code execution vulnerability where an attacker can spoof a victim client into connecting to a malicious server and execute arbitrary code on the target system due to improper authorization in the Microsoft SharePoint Server. The CVSS score was 8.0.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21400
Windows Disk Cleanup Tool Permission Escalation Vulnerability (CVE-2025-21420):
A elevation of privilege vulnerability is present in the Windows Disk Cleanup Tool, which can be exploited by a local attacker to gain SYSTEM privileges on the target system due to improper link resolution in the Windows Disk Cleanup Tool. The CVSS score is 7.8.
Official Announcement Link:
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21420
Scope of Impact
The following are some affected product versions that focus on vulnerabilities. For the scope of other products affected by vulnerabilities, please refer to the official announcement link.
| Vulnerability No. | Affected product versions |
| CVE-2025-21418 CVE-2025-21376 CVE-2025-21377 | Windows Server 2025 (Server Core installation) Windows Server 2025 Windows Server 2022, 23H2 Edition (Server Core installation) Windows Server 2022 (Server Core installation) Windows Server 2022 Windows Server 2019 (Server Core installation) Windows Server 2019 Windows Server 2016 (Server Core installation) Windows Server 2016 Windows Server 2012 R2 (Server Core installation) Windows Server 2012 R2 Windows Server 2012 (Server Core installation) Windows Server 2012 Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) Windows Server 2008 R2 for x64-based Systems Service Pack 1 Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) Windows Server 2008 for x64-based Systems Service Pack 2 Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) Windows Server 2008 for 32-bit Systems Service Pack 2 Windows 11 Version 24H2 for x64-based Systems Windows 11 Version 24H2 for ARM64-based Systems Windows 11 Version 23H2 for x64-based Systems Windows 11 Version 23H2 for ARM64-based Systems Windows 11 Version 22H2 for x64-based Systems Windows 11 Version 22H2 for ARM64-based Systems Windows 10 Version 22H2 for x64-based Systems Windows 10 Version 22H2 for ARM64-based Systems Windows 10 Version 22H2 for 32-bit Systems Windows 10 Version 21H2 for x64-based Systems Windows 10 Version 21H2 for ARM64-based Systems Windows 10 Version 21H2 for 32-bit Systems Windows 10 Version 1809 for x64-based Systems Windows 10 Version 1809 for 32-bit Systems Windows 10 Version 1607 for x64-based Systems Windows 10 Version 1607 for 32-bit Systems Windows 10 for x64-based Systems Windows 10 for 32-bit Systems |
| CVE-2025-21391 | Windows Server 2016 (Server Core installation) Windows Server 2016 Windows 10 Version 1607 for x64-based Systems Windows 10 Version 1607 for 32-bit Systems Windows 10 for x64-based Systems Windows 10 for 32-bit Systems Windows Server 2025 Windows 11 Version 24H2 for x64-based Systems Windows 11 Version 24H2 for ARM64-based Systems Windows Server 2022, 23H2 Edition (Server Core installation) Windows 11 Version 23H2 for x64-based Systems Windows 11 Version 23H2 for ARM64-based Systems Windows Server 2025 (Server Core installation) Windows 10 Version 22H2 for 32-bit Systems Windows 10 Version 22H2 for ARM64-based Systems Windows 10 Version 22H2 for x64-based Systems Windows 11 Version 22H2 for x64-based Systems Windows 11 Version 22H2 for ARM64-based Systems Windows 10 Version 21H2 for x64-based Systems Windows 10 Version 21H2 for ARM64-based Systems Windows 10 Version 21H2 for 32-bit Systems Windows Server 2022 (Server Core installation) Windows Server 2022 Windows Server 2019 (Server Core installation) Windows Server 2019 Windows 10 Version 1809 for x64-based Systems Windows 10 Version 1809 for 32-bit Systems |
| CVE-2025-21381 | Microsoft Excel 2016 (64-bit edition) Microsoft Excel 2016 (32-bit edition) Microsoft Office LTSC for Mac 2024 Microsoft Office LTSC 2024 for 64-bit editions Microsoft Office LTSC 2024 for 32-bit editions Microsoft Office LTSC 2021 for 32-bit editions Microsoft Office LTSC 2021 for 64-bit editions Microsoft Office LTSC for Mac 2021 Microsoft 365 Apps for Enterprise for 64-bit Systems Microsoft 365 Apps for Enterprise for 32-bit Systems Microsoft Office 2019 for 64-bit editions Microsoft Office 2019 for 32-bit editions Office Online Server |
| CVE-2025-21379 | Windows Server 2025 Windows 11 Version 24H2 for x64-based Systems Windows 11 Version 24H2 for ARM64-based Systems Windows Server 2025 (Server Core installation) |
| CVE-2025-21400 | Microsoft SharePoint Server Subscription Edition Microsoft SharePoint Server 2019 Microsoft SharePoint Enterprise Server 2016 |
| CVE-2025-21420 | Windows Server 2012 R2 (Server Core installation) Windows Server 2012 Windows Server 2012 (Server Core installation) Windows Server 2012 R2 Windows 10 Version 1607 for x64-based Systems Windows Server 2016 (Server Core installation) Windows 10 Version 1607 for 32-bit Systems Windows Server 2016 Windows 10 for x64-based Systems Windows 11 Version 24H2 for ARM64-based Systems Windows 11 Version 24H2 for x64-based Systems Windows 10 for 32-bit Systems Windows Server 2025 Windows Server 2022, 23H2 Edition (Server Core installation) Windows 11 Version 23H2 for x64-based Systems Windows 11 Version 23H2 for ARM64-based Systems Windows Server 2025 (Server Core installation) Windows 10 Version 1809 for x64-based Systems Windows 10 Version 22H2 for 32-bit Systems Windows 10 Version 21H2 for 32-bit Systems Windows 10 Version 1809 for 32-bit Systems Windows 10 Version 22H2 for x64-based Systems Windows 10 Version 22H2 for ARM64-based Systems Windows Server 2019 Windows 11 Version 22H2 for x64-based Systems Windows 11 Version 22H2 for ARM64-based Systems Windows 10 Version 21H2 for ARM64-based Systems Windows 10 Version 21H2 for x64-based Systems Windows Server 2019 (Server Core installation) Windows Server 2022 Windows Server 2022 (Server Core installation) |
Mitigation
At present, Microsoft has officially released security patches to fix the above vulnerabilities for supported product versions. It is strongly recommended that affected users install patches as soon as possible for protection. Download link of the official website:
https://msrc.microsoft.com/update-guide/en-us/releaseNote/2025-Feb
Note: Patch update of Windows Update may fail due to network problems, computer environment problems and other reasons. After installing the patch, users should check whether the patch is successfully updated in time.
Appendix
| Affected products | CVE No. | Vulnerability | Severity |
| Windows | CVE-2025-21376 | Windows Lightweight Directory Access Protocol (LDAP) remote code-execution vulnerability | Critical |
| Windows | CVE-2025-21379 | DHCP Client Service Remote Code Execution Vulnerability | Critical |
| Microsoft Dynamics | CVE-2025-21177 | Microsoft Dynamics 365 Sales Permission Escalation Vulnerability | Critical |
| Microsoft Office | CVE-2025-21381 | Microsoft Excel Remote Code Execution Vulnerability | Critical |
| Azure | CVE-2025-21188 | Azure Network Watcher VM Extension Permission Escalation Vulnerability | Important |
| Microsoft Visual Studio | CVE-2025-21206 | Visual Studio Installer Elevation of Privilege Vulnerability | Important |
| Windows | CVE-2025-21351 | Windows Active Directory Domain Services API Denial of Service Vulnerability | Important |
| Windows | CVE-2025-21352 | Internet Connection Sharing (ICS) denial-of-service vulnerability | Important |
| Windows | CVE-2025-21368 | Microsoft Digest Authentication Remote Code Execution Vulnerability | Important |
| Windows | CVE-2025-21369 | Microsoft Digest Authentication Remote Code Execution Vulnerability | Important |
| Windows | CVE-2025-21375 | Kernel Streaming WOW Thunk Service Driver Permission Escalation Vulnerability | Important |
| Microsoft Office | CVE-2025-21383 | Microsoft Excel Disclosure Vulnerability | Important |
| Windows | CVE-2025-21182 | Windows Resilient File System (ReFS) Deduplication Service Upgrade Vulnerability | Important |
| Windows | CVE-2025-21183 | Windows Resilient File System (ReFS) Deduplication Service Upgrade Vulnerability | Important |
| Windows | CVE-2025-21391 | Windows Storage Permission Escalation Vulnerability | Important |
| Windows | CVE-2025-21418 | Windows Ancillary Function Driver for WinSock Escalation Vulnerability | Important |
| Windows | CVE-2025-21419 | Windows Setup Files Cleanup Permission Escalation Vulnerability | Important |
| Windows | CVE-2025-21420 | Windows Disk Cleanup Tool Permission Escalation Vulnerability | Important |
| Microsoft Office | CVE-2025-24036 | Microsoft AutoUpdate (MAU) elevation of privilege vulnerability | Important |
| Visual Studio Code | CVE-2025-24039 | Visual Studio Code Permission Escalation Vulnerability | Important |
| Apps | CVE-2025-21259 | Microsoft Outlook Spoofing Vulnerability | Important |
| Microsoft Edge (Chromium-based) | CVE-2025-21342 | Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability | Important |
| Microsoft Edge (Chromium-based) | CVE-2025-21279 | Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability | Important |
| Microsoft Edge (Chromium-based) | CVE-2025-21283 | Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability | Important |
| Microsoft Edge (Chromium-based) | CVE-2025-21408 | Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability | Important |
| Device | CVE-2025-21194 | Microsoft Surface Security Feature Bypass Vulnerabilities | Important |
| Windows | CVE-2025-21208 | Windows Routing and Remote Access Service (RRAS) remote code execution vulnerability | Important |
| Windows | CVE-2025-21406 | Remote Code Execution Vulnerability of Windows Telephony Service | Important |
| Windows | CVE-2025-21407 | Remote Code Execution Vulnerability of Windows Telephony Service | Important |
| Windows | CVE-2025-21410 | Windows Routing and Remote Access Service (RRAS) remote code execution vulnerability | Important |
| Windows | CVE-2025-21190 | Remote Code Execution Vulnerability of Windows Telephony Service | Important |
| Windows | CVE-2025-21200 | Remote Code Execution Vulnerability of Windows Telephony Service | Important |
| Windows | CVE-2025-21201 | Windows Telephony Server Remote Code Execution Vulnerability | Important |
| Windows | CVE-2025-21337 | Windows NTFS Elevation of Privilege Vulnerability | Important |
| Windows | CVE-2025-21347 | Windows Deployment Services Denial of Service Vulnerability | Important |
| Windows | CVE-2025-21349 | Windows Remote Desktop Configuration Service Tamper Vulnerability | Important |
| Windows | CVE-2025-21350 | Windows Kerberos Denial of Service | Important |
| Windows | CVE-2025-21358 | Windows Core Messaging Elevation of Privileges Vulnerability | Important |
| Windows | CVE-2025-21359 | Windows Kernel Security Function Bypassing Vulnerabilities | Important |
| Windows | CVE-2025-21367 | Windows Win32 Kernel Subsystem Permission Escalation Vulnerability | Important |
| Windows | CVE-2025-21371 | Remote code execution vulnerability of Windows Telephony Service | Important |
| Windows | CVE-2025-21377 | NTLM Hash Disclosure Spoofing Vulnerability | Important |
| Microsoft Office | CVE-2025-21386 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office | CVE-2025-21387 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office | CVE-2025-21390 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office | CVE-2025-21392 | Microsoft Office Remote Code Execution Vulnerability | Important |
| Microsoft Office | CVE-2025-21394 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office | CVE-2025-21397 | Microsoft Office Remote Code Execution Vulnerability | Important |
| Microsoft Office | CVE-2025-21400 | Microsoft SharePoint Server remote code execution vulnerability | Important |
| Windows | CVE-2025-21179 | DHCP Client Service Denial of Service vulnerability | Important |
| Windows | CVE-2025-21181 | Microsoft Message Queuing (MSMQ) Denial of Service Vulnerability | Important |
| Windows | CVE-2025-21184 | Windows Core Messaging Elevation of Privileges Vulnerability | Important |
| Windows | CVE-2025-21212 | Internet Connection Sharing (ICS) denial-of-service vulnerability | Important |
| Windows | CVE-2025-21216 | Internet Connection Sharing (ICS) denial-of-service vulnerability | Important |
| Windows | CVE-2025-21254 | Internet Connection Sharing (ICS) denial-of-service vulnerability | Important |
| Apps | CVE-2025-21322 | Microsoft PC Manager Elevation of Privilege Vulnerability | Important |
| Windows | CVE-2025-21414 | Windows Core Messaging Elevation of Privilege Vulnerability | Important |
| Windows | CVE-2025-21373 | Windows Installer Elevation of Privilege Vulnerability | Important |
| Visual Studio Code – JS Debug Extension | CVE-2025-24042 | Visual Studio Code JS Debug Extension Permission Escalation Vulnerability | Important |
| Azure | CVE-2025-21198 | Microsoft High Performance Compute (HPC) Pack Remote Execution Vulnerability | Important |
| Microsoft Edge for iOS,Microsoft Edge for Android | CVE-2025-21253 | Microsoft Edge for IOS and Android Spoofing | Moderate |
| Microsoft Edge (Chromium-based) | CVE-2025-21267 | Microsoft Edge (Chromium-based) spoofing vulnerability | Low |
| Microsoft Edge (Chromium-based) | CVE-2025-21404 | Microsoft Edge (Chromium-based) spoofing vulnerability | Low |
Statement
This advisory is only used to describe a potential risk. NSFOCUS does not provide any commitment or promise on this advisory. NSFOCUS and the author will not bear any liability for any direct and/or indirect consequences and losses caused by transmitting and/or using this advisory. NSFOCUS reserves all the rights to modify and interpret this advisory. Please include this statement paragraph when reproducing or transferring this advisory. Do not modify this advisory, add/delete any information to/from it, or use this advisory for commercial purposes without permission from NSFOCUS.
About NSFOCUS
NSFOCUS, a pioneering leader in cybersecurity, is dedicated to safeguarding telecommunications, Internet service providers, hosting providers, and enterprises from sophisticated cyberattacks.
Founded in 2000, NSFOCUS operates globally with over 4000 employees at two headquarters in Beijing, China, and Santa Clara, CA, USA, and over 50 offices worldwide. It has a proven track record of protecting over 25% of the Fortune Global 500 companies, including four of the five largest banks and six of the world’s top ten telecommunications companies.
Leveraging technical prowess and innovation, NSFOCUS delivers a comprehensive suite of security solutions, including the Intelligent Security Operations Platform (ISOP) for modern SOC, DDoS Protection, Continuous Threat Exposure Management (CTEM) Service and Web Application and API Protection (WAAP). All the solutions and services are augmented by the Security Large Language Model (SecLLM), ML, patented algorithms and other cutting-edge research achievements developed by NSFOCUS.
