CVE-2026-108399

Awaiting Analysis Awaiting Analysis - Queue

Heap-based Buffer Overflow in Windows Hyper-V

Publication date: 2026-10-13

Last updated on: 2026-10-16

Assigner: Microsoft Corporation

Description

Heap-based buffer overflow in Windows Hyper-V allows an authorized attacker to elevate privileges locally.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-10-13

Last Modified

2026-10-16

Generated

2026-10-19

AI Q&A

2026-10-14

EPSS Evaluated

2026-10-18

NVD

CVE-2026-108399

EUVD

EUVD-2026-99081

Affected Vendors & Products

Vendor	Product	Version / Range
Microsoft	Windows	10 Version 1607 10.0.14393.0
Microsoft	Windows	10 Version 1809 10.0.17763.0
Microsoft	Windows	10 Version 21H2 10.0.19044.0
Microsoft	Windows	10 Version 22H2 10.0.19045.0
Microsoft	Windows	11 version 23H2 10.0.22631.0
Microsoft	Windows	11 Version 23H2 10.0.22631.0
Microsoft	Windows	11 Version 24H2 10.0.26100.0
Microsoft	Windows	11 Version 25H2 10.0.26200.0
Microsoft	Windows	11 version 26H1 10.0.28000.0
Microsoft	Windows	11 Version 26H2 10.0.26300.0
Microsoft	Windows	Server 2012 6.2.9200.0
Microsoft	Windows	Server 2012 (Server Core installation) 6.2.9200.0
Microsoft	Windows	Server 2012 R2 6.3.9600.0
Microsoft	Windows	Server 2012 R2 (Server Core installation) 6.3.9600.0
Microsoft	Windows	Server 2016 10.0.14393.0
Microsoft	Windows	Server 2016 (Server Core installation) 10.0.14393.0
Microsoft	Windows	Server 2019 10.0.17763.0
Microsoft	Windows	Server 2019 (Server Core installation) 10.0.17763.0
Microsoft	Windows	Server 2022 10.0.20348.0
Microsoft	Windows	Server 2025 10.0.26100.0
Microsoft	Windows	Server 2025 (Server Core installation) 10.0.26100.0

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-122	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().

Attack-Flow Graph

Executive Summary

This is a heap-based buffer overflow vulnerability in Windows Hyper-V. It allows an authorized attacker with local access to elevate their privileges on the system. The overflow occurs in memory allocated for Hyper-V operations, potentially enabling the attacker to execute arbitrary code with higher system permissions.

Impact Analysis

If exploited, this vulnerability could allow an attacker to gain elevated privileges on your system. This means they could bypass security controls, install malicious software, access sensitive data, or take full control of the affected machine. The impact is higher if the system runs critical workloads or handles sensitive information.

Mitigation Strategies

Apply the latest security updates from Microsoft for Hyper-V and Windows systems to patch the heap-based buffer overflow vulnerability.

Hi! I’m here to help you understand CVE-2026-108399. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70