Windows Fast FAT File System Driver Remote Code Execution Vulnerability

cisa required action Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

1. 2025-03-11 0-day patched (Project Zero)
2. 2025-03-11 Added to CISA KEV
3. 2025-03-11 Published
4. 2025-03-14 CISA SSVC: exploitation active
5. 2025-04-01 CISA patch deadline

Added

19 mo ago (2025-03-11)

Patch by

2025-04-01 (19 mo ago)

Ransomware

Not known

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Vendor, product

Microsoft, Windows

CISA name

Microsoft Windows Fast FAT File System Driver Integer Overflow Vulnerability

Detected in real attacks while still unknown to the vendor and the public, per Google Project Zero's 0day In-the-Wild tracker.

Patched

2025-03-11

Details

project zero tracker

How it is exploited and what it leads to, in MITRE ATT&CK terms.

• T1091 Replication Through Removable Media exploitation
• T1059 Command and Scripting Interpreter primary impact

kev release 2025-07-28, att&ck v16.1. KEV to ATT&CK mappings by the MITRE Center for Threat-Informed Defense (Mappings Explorer, Apache-2.0). © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. Terms of use

Exploitation

Active, exploited in the wild

Automatable

no

Technical impact

total

Assessed

19 mo ago (2025-03-14)

3.89% chance of exploitation in the next 30 days, higher than 90% of all scored CVEs (FIRST EPSS, 2026-11-08).

• vicarius.io https://www.vicarius.io/vsociety/posts/cve-2025-24985-integer-overflow-vulnerability-in-microsoft-windows-fast-fat-driver-detection-script referenced PoC, tagged "exploit" by a source, unverified

• Microsoft Windows 10 Version 1507
• Microsoft Windows 10 Version 1607
• Microsoft Windows 10 Version 1809
• Microsoft Windows 10 Version 21H2
• Microsoft Windows 10 Version 22H2
• Microsoft Windows 11 version 22H2
• Microsoft Windows 11 version 22H3
• Microsoft Windows 11 Version 23H2
• Microsoft Windows 11 Version 24H2
• Microsoft Windows Server 2008 R2 Service Pack 1
• Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation)
• Microsoft Windows Server 2008 Service Pack 2
• Microsoft Windows Server 2008 Service Pack 2 (Server Core installation)
• Microsoft Windows Server 2012
• Microsoft Windows Server 2012 (Server Core installation)
• Microsoft Windows Server 2012 R2
• Microsoft Windows Server 2012 R2 (Server Core installation)
• Microsoft Windows Server 2016
• Microsoft Windows Server 2016 (Server Core installation)
• Microsoft Windows Server 2019
• Microsoft Windows Server 2019 (Server Core installation)
• Microsoft Windows Server 2022
• Microsoft Windows Server 2022, 23H2 Edition (Server Core installation)
• Microsoft Windows Server 2025
• Microsoft Windows Server 2025 (Server Core installation)

Weakness

• CWE-190 Integer Overflow or Wraparound
• CWE-122 Heap-based Buffer Overflow

• msrc.microsoft.com /update-guide/vulnerability/CVE-2025-24985

  vendor-advisory, patch

• vicarius.io /vsociety/posts/cve-2025-24985-integer-overflow-vulnerability-in-microsoft-windows-fast-fat-driver-detection-s

  exploit, third-party-advisory

• cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-24985

  government-resource, us-government-resource

• vicarius.io /vsociety/posts/cve-2025-24985-integer-overflow-vulnerability-in-microsoft-windows-fast-fat-driver-mitigation-

  mitigation, third-party-advisory

• CVE List CVE-2025-24985
• NVD CVE-2025-24985

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.