⚠ Actively exploited
Added to CISA KEV on 2025-01-14. Federal agencies required to patch by 2025-02-04. Required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable..

CVE-2025-21333 — Heap-based Buffer Overflow in Microsoft Windows 10 Version 21h2

CWE-122 — Heap-based Buffer Overflow18 documents12 sources
Severity
7.8HIGHNVD
EPSS
81.3%
top 0.83%
CISA KEV
KEV
Added 2025-01-14
Due 2025-02-04
Exploit
PoC available
Public exploit / PoC exists
Affected products
23
Microsoft Windows 10 Version 21h2Microsoft Windows 10 Version 22h2Microsoft Windows 11 Version 22h2+20 more
Timeline
PublishedJan 14
KEV addedJan 14
KEV dueFeb 4
Latest updateSep 16
CISA Required Action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Description

Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9

Affected Packages23 packages

▶NVDmicrosoft/windows< 10.0.25398.1369+1
▶NVDmicrosoft/windows_10_21h2< 10.0.19044.5371
▶NVDmicrosoft/windows_10_22h2< 10.0.19045.5371
▶NVDmicrosoft/windows_11_22h2< 10.0.22621.4751
▶NVDmicrosoft/windows_11_23h2< 10.0.22631.4751

Patches

Patch: msrc.microsoft.com ↗

🔴Vulnerability Details

2
GHSA
GHSA-gjv6-pfh4-3rff: Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability↗2025-01-14
▶
VulnCheck
Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow Vulnerability↗2025
▶

💥Exploits & PoCs

1
Exploit-DB
Microsoft Windows Server 2025 Hyper-V NT Kernel Integration VSP - Elevation of Privilege↗2025-09-16
▶

📋Vendor Advisories

2
Microsoft
Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability↗2025-01-14
▶
CISA
Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow Vulnerability↗2025-01-14
▶

🕵️Threat Intelligence

12
Securelist
Vulnerability landscape analysis for Q1 2025↗2025-05-30
▶
Securelist
Exploits and vulnerabilities in Q1 2025↗2025-05-30
▶
Qualys
Zero-Day Vulnerability Protection | Detect &amp; Stop Threats | Qualys↗2025-04-18
▶
Qualys
Zero-Day Vulnerability Protection | Detect & Stop Threats | Qualys↗2025-04-18
▶
Tenable
Cybersecurity Snapshot: CISA Calls for Stamping Out Buffer Overflow Vulnerabilities, as Europol Tells Banks To Prep For Quantum Threat↗2025-02-14
▶
CVE-2025-21333 — Heap-based Buffer Overflow | cvebase