# MA-1286.032025: MyCERT Advisory - Privilege Escalation Vulnerability in Windows Disk Cleanup Tool

**Date:** 12 Mar 2025  
**Source:** https://www.mycert.org.my/portal/advisory?id=MA-1286.032025  
**Advisory ID:** MA-1286.032025

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**1.0 Introduction**
Recently, Microsoft released an advisory to address a high-severity vulnerability, tracked as CVE-2025-21420, has been identified in the Windows Disk Cleanup Toll (cleanmgr.exe).
**2.0 Impact**
This vulnerability allowing attackers to escalate privileges to the SYSTEM.
**3.0 Affected Products**
Windows Disk Cleanup Tool (cleanmgr.exe)
**4.0 Recommendations**
CyberSecurity Malaysia also encourages users and administrators to review [Microsoft Security Update Guide](https://msrc.microsoft.com/update-guide/)for more information and apply the necessary updates.
Kindly refer to the following URL:  <https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21420>
Generally, we advise users to be updated with the latest security announcements by the vendor and follow best practice security policies to determine which updates should be applied.
For further enquiries, please contact Cyber999 Incident Response Centre through the following channels:
E-mail: cyber999[at]cybersecurity.my 
Phone: 1-300-88-2999 (monitored during business hours) 
Mobile: +60 19 2665850 (24x7 call incident reporting) 
Business Hours: Mon - Fri 08:30 -17:30 the MYT 
Web: [https://www.mycert.org.my](https://www.mycert.org.my/)
**5.0    References**
- <https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21420>
- <https://msrc.microsoft.com/update-guide/>