CriticalCVE-2025-24993

    Windows NTFS Remote Code Execution Vulnerability (CVE-2025-24993)

    Published Last modified In CISA KEV since Sources: pwn.watch, Msrc Update Guide, CVE.org

    What is affected, what to do

    Heap-based buffer overflow in Windows NTFS allows an unauthorized attacker to execute code locally.

    The vulnerability is being actively exploited; treat it as a priority. Update Microsoft Windows 10 Version 1507 to version 10.0.10240.20947, Microsoft Windows 10 Version 1607 to version 10.0.14393.7876, Microsoft Windows 10 Version 1809 to version 10.0.17763.7009. Immediate actions, mitigation and detection rules are in the runbook below.

    Affected
    • Microsoft Windows 10 Version 1507 lt 10.0.10240.0..10.0.10240.20947
    • Microsoft Windows 10 Version 1607 lt 10.0.14393.0..10.0.14393.7876
    • Microsoft Windows 10 Version 1809 lt 10.0.17763.0..10.0.17763.7009
    • Microsoft Windows 10 Version 21H2 lt 10.0.19044.0..10.0.19044.5608
    • Microsoft Windows 10 Version 22H2 lt 10.0.19045.0..10.0.19045.5608
    • Microsoft Windows 11 version 22H2 lt 10.0.22621.0..10.0.22621.5039
    • Microsoft Windows 11 version 22H3 lt 10.0.22631.0..10.0.22631.5039
    • Microsoft Windows 11 Version 23H2 lt 10.0.22631.0..10.0.22631.5039
    • Microsoft Windows 11 Version 24H2 lt 10.0.26100.0..10.0.26100.3476
    • Microsoft Windows Server 2008 R2 Service Pack 1 lt 6.1.7601.0..6.1.7601.27618
    • Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation) lt 6.1.7601.0..6.1.7601.27618
    • Microsoft Windows Server 2008 Service Pack 2 lt 6.0.6003.0..6.0.6003.23168
    • Microsoft Windows Server 2008 Service Pack 2 (Server Core installation) lt 6.0.6003.0..6.0.6003.23168
    • Microsoft Windows Server 2012 lt 6.2.9200.0..6.2.9200.25368
    • Microsoft Windows Server 2012 (Server Core installation) lt 6.2.9200.0..6.2.9200.25368
    • Microsoft Windows Server 2012 R2 lt 6.3.9600.0..6.3.9600.22470
    • Microsoft Windows Server 2012 R2 (Server Core installation) lt 6.3.9600.0..6.3.9600.22470
    • Microsoft Windows Server 2016 lt 10.0.14393.0..10.0.14393.7876
    • Microsoft Windows Server 2016 (Server Core installation) lt 10.0.14393.0..10.0.14393.7876
    • Microsoft Windows Server 2019 lt 10.0.17763.0..10.0.17763.7009
    • Microsoft Windows Server 2019 (Server Core installation) lt 10.0.17763.0..10.0.17763.7009
    • Microsoft Windows Server 2022 lt 10.0.20348.0..10.0.20348.3328
    • Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) lt 10.0.25398.0..10.0.25398.1486
    • Microsoft Windows Server 2025 lt 10.0.26100.0..10.0.26100.3476
    • Microsoft Windows Server 2025 (Server Core installation) lt 10.0.26100.0..10.0.26100.3476
    Fixed in
    • Microsoft Windows 10 Version 1507 10.0.10240.20947
    • Microsoft Windows 10 Version 1607 10.0.14393.7876
    • Microsoft Windows 10 Version 1809 10.0.17763.7009
    • Microsoft Windows 10 Version 21H2 10.0.19044.5608
    • Microsoft Windows 10 Version 22H2 10.0.19045.5608
    • Microsoft Windows 11 version 22H2 10.0.22621.5039
    • Microsoft Windows 11 version 22H3 10.0.22631.5039
    • Microsoft Windows 11 Version 23H2 10.0.22631.5039
    • Microsoft Windows 11 Version 24H2 10.0.26100.3476
    • Microsoft Windows Server 2008 R2 Service Pack 1 6.1.7601.27618
    • Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation) 6.1.7601.27618
    • Microsoft Windows Server 2008 Service Pack 2 6.0.6003.23168
    • Microsoft Windows Server 2008 Service Pack 2 (Server Core installation) 6.0.6003.23168
    • Microsoft Windows Server 2012 6.2.9200.25368
    • Microsoft Windows Server 2012 (Server Core installation) 6.2.9200.25368
    • Microsoft Windows Server 2012 R2 6.3.9600.22470
    • Microsoft Windows Server 2012 R2 (Server Core installation) 6.3.9600.22470
    • Microsoft Windows Server 2016 10.0.14393.7876
    • Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.7876
    • Microsoft Windows Server 2019 10.0.17763.7009
    • Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.7009
    • Microsoft Windows Server 2022 10.0.20348.3328
    • Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.1486
    • Microsoft Windows Server 2025 10.0.26100.3476
    • Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.3476

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    7.8

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v3

    7.8

    CVSS v3

    Severity High on the scale from 0 to 10.

    Source: pwn.watch, Msrc Update Guide, CVE.org

    2.2 %

    EPSS score

    Moderate — model estimates 1-10% exploitation likelihood.

    Source: FIRST EPSS, percentile 82.5

    Show all metrics
    Severity
    Critical
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    201.66 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    actively exploitedSource: VulnCheck KEV (opens in a new tab) How we classify
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    7.8 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    7.8
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    2.2 %
    Moderate — model estimates 1-10% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    82.5
    Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    Actively exploited
    Published
    In CISA KEV since

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-122

    Response and mitigation

    Why act now?

    Prioritisation rationale

    Microsoft disclosed this as a zero-day already being exploited at release, which is why it went straight onto KEV. Exploitation needs local access and user interaction, typically a crafted VHD delivered by phishing or download. It requires no prior privileges, and success means full compromise of confidentiality, integrity and availability. Exploitation likelihood is elevated but not in the top tier, and CISA lists no known ransomware use. For organisations with large client fleets, VDI estates and heavy phishing exposure, treat it as high priority and close it within your emergency patch window (≤ 7 days). Server estates without interactive users rank lower but should not be skipped.

    1. Runbook step 1

      Immediate response (0-24 h)

      • Deploy the March 2025 Patch Tuesday cumulative update with priority. Target builds: Windows 10 1507 ≥ 10.0.10240.20947, 1607 ≥ 10.0.14393.7876, 1809 ≥ 10.0.17763.7009, 21H2/22H2 ≥ 10.0.19044.5608 / 10.0.19045.5608, Windows 11 22H2 ≥ 10.0.22621.5039, 22H3/23H2 ≥ 10.0.22631.5039. Look up the exact KB per build in the Microsoft (MSRC) advisory.
      • Reconcile inventory. Use Intune/SCCM/Defender TVM to list every host below the target build, e.g. DeviceInfo | where OSBuild < 5608 and OSVersion == "10.0.19045". Also check Windows Server editions sharing the same build base (14393, 17763) against the vendor advisory.
      • Patch high-exposure endpoints first. This means privileged access workstations, jump hosts, VDI/RDS session hosts and users with heavy mail or download exposure. Microsoft describes the attack as mounting a crafted virtual hard disk (VHD/VHDX).
      • Block crafted disk images at the perimeter immediately. Block or quarantine .vhd, .vhdx and .avhdx files at the mail gateway and web proxy. Include archives (ZIP/7z/ISO) that contain such files.
      • Purge images already delivered. Search mailboxes for VHD/VHDX attachments from the last 30 days, remove them, and flag recipient endpoints for triage.

    2. Runbook step 2

      Mitigation layers

      • Configuration (endpoint): Remove the Explorer "Mount" verb for VHD files via a GPO registry preference. The keys are HKCR\Windows.VhdFile\shell\mount and HKCR\Windows.VhdxFile\shell\mount (pilot first). This stops a double-click from attaching the image.
      • IAM/least privilege: Strip local admin rights and enforce LAPS. The goal is that standard users cannot run Mount-DiskImage or diskpart attach vdisk, which narrows the routes for attaching a crafted VHD.
      • Application control: Use WDAC/AppLocker to deny execution from removable and virtual volumes. Also enable the Defender ASR rule "Block executable files from running unless they meet a prevalence, age, or trusted list criterion" in block mode.
      • Mark-of-the-Web and SmartScreen: Make sure MotW survives extraction (current 7-Zip with Zone.Id propagation enabled). Enforce SmartScreen via GPO.
      • Network and segmentation: Separate VDI and admin networks from general internet access. Use a File Server Resource Manager (FSRM) file screen to block VHD files on SMB shares.

    3. Runbook step 3

      Detection rules

      • VHDMP event log: Collect Microsoft-Windows-VHDMP-Operational and alert on attach/surface events not originating from Hyper-V or backup processes. Verify the event IDs on your builds before rollout. This is especially useful on clients where VHD use is unusual.
      • Process creation (Sysmon EID 1 / Security 4688): Watch for powershell.exe running Mount-DiskImage or Mount-VHD, and for diskpart.exe with attach vdisk. Sigma shape: CommandLine|contains: ['Mount-DiskImage','attach vdisk'] and ParentImage not in known admin tooling.
      • File creation (Sysmon EID 11/15): Look for .vhd or .vhdx written to \Downloads\, \AppData\Local\Temp\ or \Content.Outlook\, especially with a Zone.Identifier stream (ZoneId=3). KQL: DeviceFileEvents | where FileName endswith ".vhd" or FileName endswith ".vhdx" | where FolderPath has_any ("Downloads","Temp","Outlook").
      • EDR process ancestry: Flag binaries launched from a freshly mounted drive letter (parent explorer.exe), and unexpected SYSTEM-context child processes shortly after a mount.
      • Stability signals: Bugchecks or unexpected reboots (System Event ID 41, 1001 referencing ntfs.sys) shortly after an image mount may indicate failed exploitation attempts.

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    Heap-based buffer overflow in Windows NTFS allows an unauthorized attacker to execute code locally.

    Source: pwn.watch, Microsoft Security Update Guide, NVD (NIST), cvelistv5, CISA KEV Catalog, CVE.org (MITRE)

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    MicrosoftWindows 10 Version 1507
    • 10.0.10240.0 – < 10.0.10240.20947
    • 10.0.10240.20947
    MicrosoftWindows 10 Version 1607
    • 10.0.14393.0 – < 10.0.14393.7876
    • 10.0.14393.7876
    MicrosoftWindows 10 Version 1809
    • 10.0.17763.0 – < 10.0.17763.7009
    • 10.0.17763.7009
    MicrosoftWindows 10 Version 21H2
    • 10.0.19044.0 – < 10.0.19044.5608
    • 10.0.19044.5608
    MicrosoftWindows 10 Version 22H2
    • 10.0.19045.0 – < 10.0.19045.5608
    • 10.0.19045.5608
    MicrosoftWindows 11 version 22H2
    • 10.0.22621.0 – < 10.0.22621.5039
    • 10.0.22621.5039
    MicrosoftWindows 11 version 22H3
    • 10.0.22631.0 – < 10.0.22631.5039
    • 10.0.22631.5039
    MicrosoftWindows 11 Version 23H2
    • 10.0.22631.0 – < 10.0.22631.5039
    • 10.0.22631.5039
    MicrosoftWindows 11 Version 24H2
    • 10.0.26100.0 – < 10.0.26100.3476
    • 10.0.26100.3476
    MicrosoftWindows Server 2008 R2 Service Pack 1
    • 6.1.7601.0 – < 6.1.7601.27618
    • 6.1.7601.27618
    MicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)
    • 6.1.7601.0 – < 6.1.7601.27618
    • 6.1.7601.27618
    MicrosoftWindows Server 2008 Service Pack 2
    • 6.0.6003.0 – < 6.0.6003.23168
    • 6.0.6003.23168
    MicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)
    • 6.0.6003.0 – < 6.0.6003.23168
    • 6.0.6003.23168
    MicrosoftWindows Server 2012
    • 6.2.9200.0 – < 6.2.9200.25368
    • 6.2.9200.25368
    MicrosoftWindows Server 2012 (Server Core installation)
    • 6.2.9200.0 – < 6.2.9200.25368
    • 6.2.9200.25368
    MicrosoftWindows Server 2012 R2
    • 6.3.9600.0 – < 6.3.9600.22470
    • 6.3.9600.22470
    MicrosoftWindows Server 2012 R2 (Server Core installation)
    • 6.3.9600.0 – < 6.3.9600.22470
    • 6.3.9600.22470
    MicrosoftWindows Server 2016
    • 10.0.14393.0 – < 10.0.14393.7876
    • 10.0.14393.7876
    MicrosoftWindows Server 2016 (Server Core installation)
    • 10.0.14393.0 – < 10.0.14393.7876
    • 10.0.14393.7876
    MicrosoftWindows Server 2019
    • 10.0.17763.0 – < 10.0.17763.7009
    • 10.0.17763.7009
    MicrosoftWindows Server 2019 (Server Core installation)
    • 10.0.17763.0 – < 10.0.17763.7009
    • 10.0.17763.7009
    MicrosoftWindows Server 2022
    • 10.0.20348.0 – < 10.0.20348.3328
    • 10.0.20348.3328
    MicrosoftWindows Server 2022, 23H2 Edition (Server Core installation)
    • 10.0.25398.0 – < 10.0.25398.1486
    • 10.0.25398.1486
    MicrosoftWindows Server 2025
    • 10.0.26100.0 – < 10.0.26100.3476
    • 10.0.26100.3476
    MicrosoftWindows Server 2025 (Server Core installation)
    • 10.0.26100.0 – < 10.0.26100.3476
    • 10.0.26100.3476

    Vendors and products

    Affected operating systems

    Affected operating systems
    Windowsmicrosoftwindows_10_1507—
    Windowsmicrosoftwindows_10_1607—
    Windowsmicrosoftwindows_10_1809—
    Windowsmicrosoftwindows_10_21h2—
    Windowsmicrosoftwindows_10_22h2—
    Windowsmicrosoftwindows_11_22h2—
    Windowsmicrosoftwindows_11_23h2—
    Windowsmicrosoftwindows_11_24h2—
    Windowsmicrosoftwindows_server_2008r2
    Windowsmicrosoftwindows_server_2008—
    Windowsmicrosoftwindows_server_2012r2
    Windowsmicrosoftwindows_server_2012—
    Windowsmicrosoftwindows_server_2016—
    Windowsmicrosoftwindows_server_2019—
    Windowsmicrosoftwindows_server_2022—
    Windowsmicrosoftwindows_server_2022_23h2—
    Windowsmicrosoftwindows_server_2025—

    Weakness classes (CWE)

    • CWE-122Heap-based Buffer Overflow

      Variant

      A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

      Entry at MITRE CWE-122

    Public exploit references

    Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

    Public exploit references
    CISA KEV CatalogCISA Known Exploited Vulnerability (opens in a new tab)cisa.govactively exploited

    References & sources

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    One NVD translation into another language is hidden.

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    Badge preview for CVE-2025-24993
    <a href="https://intel.neosec.eu/en/cve/CVE-2025-24993"><img src="https://intel.neosec.eu/badge/cve/CVE-2025-24993.svg?lang=en" alt="CVE-2025-24993 – NEOSEC Intel" height="20"></a>