Cyber Posture

CVE-2025-21391

HighCISA KEVActive Exploitation

Published: 11 February 2025

Published
11 February 2025
Modified
27 October 2025
KEV Added
11 February 2025
Patch
CVSS Score 7.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS Score 0.0472 89.5th percentile
Risk Priority 37 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21391 is a high-severity Link Following (CWE-59) vulnerability in Microsoft Windows 10 1507. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 10.5% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities 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

What attackers do: exploitation maps to Exploitation for Privilege Escalation (T1068). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Timely remediation of identified flaws, such as applying the Microsoft security update, directly eliminates the Windows Storage elevation of privilege vulnerability.

detect

Vulnerability scanning identifies the presence of CVE-2025-21391 in Windows systems, enabling proactive patching before exploitation.

prevent

Enforcing least privilege restricts the actions of low-privileged local attackers, reducing the potential impact of successful privilege escalation.

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Local Windows Storage EoP vulnerability (CWE-59 link following) directly enables exploitation for privilege escalation from low-privileged local context.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Windows Storage Elevation of Privilege Vulnerability

Deeper analysisAI

CVE-2025-21391 is a Windows Storage Elevation of Privilege Vulnerability affecting the Windows Storage component in Microsoft Windows operating systems. Published on 2025-02-11, it has a CVSS v3.1 base score of 7.1 (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H) and is associated with CWE-59.

The vulnerability can be exploited by a local attacker who already possesses low-level privileges on the target system. Exploitation requires low complexity and no user interaction, enabling the attacker to elevate privileges with high impacts on system integrity and availability, though confidentiality remains unaffected.

Microsoft's update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21391 provides details on available security updates to address the issue. The vulnerability is also listed in CISA's Known Exploited Vulnerabilities Catalog at https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21391, indicating real-world exploitation and requiring mitigation by federal civilian executive branch agencies.

Details

CWE(s)
KEV Date Added
11 February 2025

Affected Products

microsoft
windows 10 1507
≤ 10.0.10240.20915 · ≤ 10.0.10240.20915
microsoft
windows 10 1607
≤ 10.0.14393.7785 · ≤ 10.0.14393.7785
microsoft
windows 10 1809
≤ 10.0.17763.6893 · ≤ 10.0.17763.6893
microsoft
windows 10 21h2
≤ 10.0.19044.5487
microsoft
windows 10 22h2
≤ 10.0.19045.5487
microsoft
windows 11 22h2
≤ 10.0.22621.4890
microsoft
windows 11 23h2
≤ 10.0.22631.4890
microsoft
windows 11 24h2
≤ 10.0.26100.3107
microsoft
windows server 2016
≤ 10.0.14393.7785
microsoft
windows server 2019
≤ 10.0.17763.6893
+3 more product configuration(s) — see NVD for full list

CVEs Like This One

CVE-2025-21420Same product: Microsoft Windows 10 1507
CVE-2025-21373Same product: Microsoft Windows 10 1507
CVE-2025-21419Same product: Microsoft Windows 10 1507
CVE-2025-59230Same product: Microsoft Windows 10 1507both on KEV
CVE-2025-24990Same product: Microsoft Windows 10 1507both on KEV
CVE-2025-21418Same product: Microsoft Windows 10 1607both on KEV
CVE-2026-21519Same product: Microsoft Windows 10 1607both on KEV
CVE-2026-21533Same product: Microsoft Windows 10 1607both on KEV
CVE-2025-21331Same product: Microsoft Windows 10 1507
CVE-2026-25187Same product: Microsoft Windows 10 1607

References