Cyber Resilience

CVE-2025-21271

Memory Safety in Microsoft Windows 10 1809 ≤ 10.0.17763.6775

Published
14 January 2025
Modified
27 January 2025
Patch / advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0054 43th percentile
Risk Priority 57 floored blend · peak EPSS

Summary

CVE-2025-21271 is a high-severity Buffer Over-read (CWE-126) vulnerability in Microsoft Windows 10 1809. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Credential Dumping (T1003); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-21271 is an Elevation of Privilege vulnerability in the Windows Cloud Files Mini Filter Driver. This flaw, published on 2025-01-14, carries 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) and is associated with CWE-126 and NVD-CWE-noinfo. It affects Windows systems utilizing the Cloud Files Mini Filter Driver component.

A local attacker with low privileges can exploit this vulnerability due to its local attack vector and low complexity requirements, with no user interaction needed. Successful exploitation grants high impacts on confidentiality, integrity, and availability, enabling the attacker to elevate privileges, potentially achieving full system compromise.

Microsoft's Security Response Center provides an update guide detailing mitigation and patching information for CVE-2025-21271 at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21271.

EU & UK References

Vulnerability Data

Windows Cloud Files Mini Filter Driver Elevation of Privilege Vulnerability

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-36904Same product: Microsoft Windows 10 1809
CVE-2026-50383Same product: Microsoft Windows 10 1809
CVE-2025-62461Same product: Microsoft Windows 10 1809
CVE-2025-62462Same product: Microsoft Windows 10 1809
CVE-2026-42828Same product: Microsoft Windows 10 1809
CVE-2025-62464Same product: Microsoft Windows 10 1809
CVE-2023-35324Same product: Microsoft Windows 10 1809
CVE-2026-26184Same product: Microsoft Windows 10 1809
CVE-2023-32085Same product: Microsoft Windows 10 1809
CVE-2023-36581Same product: Microsoft Windows 10 1809

Affected Assets

microsoft
windows 10 1809
≤ 10.0.17763.6775 · ≤ 10.0.17763.6775
microsoft
windows 10 21h2
≤ 10.0.19044.5371
microsoft
windows 10 22h2
≤ 10.0.19045.5371
microsoft
windows server 2019
≤ 10.0.17763.6775
microsoft
windows server 2022
≤ 10.0.20348.3091

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (static analysis, fuzzing, bounds checking tests) directly finds buffer over-read flaws.

Engineering principles such as memory-safe design and bounds-checked abstractions structurally stop introduction of out-of-bounds reads.

Process isolation limits the blast radius of an over-read to the compromised domain.

Input validation enforces length and index constraints that prevent many externally triggered over-reads.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure development practices directly prevent introduction of buffer over-read weaknesses.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover buffer over-read flaws via scanning or review.

PR.PS-02 partial match
prevents

Patching or replacing vulnerable software removes known instances of buffer over-read bugs.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development can detect buffer over-reads before release.

prevents

Secure SDLC mandates input validation and bounds checking that can prevent buffer over-reads.

prevents

Application security requirements can specify buffer-size and bounds-checking rules.

prevents

Secure architecture principles include memory-safety and bounds-checking design choices.

prevents

Secure coding standards directly require bounds-checked buffer access, mitigating over-reads.

References