CVE-2025-21420
Published: 11 February 2025
Summary
CVE-2025-21420 is a high-severity Link Following (CWE-59) vulnerability in Microsoft Windows 10 1507. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 2.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and AC-6 (Least Privilege).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly remediates the improper link resolution vulnerability in the Windows Disk Cleanup Tool by requiring timely application of the Microsoft security update.
Enforces least privilege on user accounts and processes, limiting the scope and impact of local low-privilege attackers attempting to exploit the elevation vulnerability.
Implements memory protections such as non-executable memory and ASLR to mitigate arbitrary code execution that may result from successful privilege escalation via improper file access.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The CVE describes a local elevation of privilege vulnerability in Windows Disk Cleanup Tool via improper link resolution (CWE-59), allowing low-privileged attackers to gain full system control. This directly maps to Exploitation for Privilege Escalation.
NVD Description
Windows Disk Cleanup Tool Elevation of Privilege Vulnerability
Deeper analysisAI
CVE-2025-21420 is an elevation of privilege vulnerability in the Windows Disk Cleanup Tool. It stems from improper link resolution before file access, classified under CWE-59. The vulnerability affects Windows systems and has a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high impact on confidentiality, integrity, and availability when exploited.
A local attacker with low-privilege access can exploit this vulnerability without user interaction. Successful exploitation allows the attacker to elevate privileges, potentially gaining full system control by modifying critical files or executing arbitrary code with elevated rights.
The Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21420 provides details on patching, recommending that affected systems apply the available security update to mitigate the issue.
Details
- CWE(s)