Windows
CVE-2026-21244
HIGH
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessAuthenticate as local user
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ExploitInteract with Hyper-V management interface
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ExecutionTrigger heap buffer overflow
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ImpactExecute arbitrary code with hypervisor privileges
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Heap buffer bounds checking
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Local user account access to Windows Hyper-V with permission to interact with hypervisor management interfaces. Requires user interaction (UI:R) to trigger vulnerable Hyper-V feature or component. |
| Impact | CVSS 7.3 (HIGH). Attack vector: Local. Complexity: Low. Privileges required: Low. User interaction: Required. Exploitable via local access. |
| Exploit ScenarioDerived | An attacker could exploit this vulnerability to compromise the affected system. |
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Alert meAnalysisAIv1 – Mar 12, 2026
Heap overflow in Windows Hyper-V enables authenticated local users to achieve arbitrary code execution with high privileges (CVSS 7.3). Exploitation requires user interaction and local system access, affecting Windows 10 1809 and Windows Server 2025. No patch is currently available.
Earlier versions of this analysis (1)
Heap-based buffer overflow in Windows Hyper-V allows an authorized attacker to execute code locally. [CVSS 7.3 HIGH]
RemediationAI
Monitor vendor advisories for a patch. Enable ASLR, DEP/NX, and stack canaries where possible.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 13 packages in microsoft
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Classified as CWE-122 (Heap-based Buffer Overflow). Affects Windows 10 1607. Heap-based buffer overflow in Windows Hyper-V allows an authorized attacker to execute code locally.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
Heap-based buffer overflow in Windows Hyper-V allows an authorized attacker to execute code locally.
Executive ViewAI
A heap-based buffer overflow vulnerability in Windows Hyper-V poses a local code execution risk to organizations running virtualized infrastructure. This vulnerability requires local access and authenticated credentials, limiting exposure to insider threats and compromised accounts with system access. Unpatched Hyper-V hosts could allow attackers to escalate privileges and gain control of virtual machines and host systems.
Restrict local administrative access and enforce multi-factor authentication for Hyper-V management accounts; disable unnecessary Hyper-V features and roles not in active use; isolate Hyper-V management networks from general user networks; implement behavioral monitoring on Hyper-V hosts to detect exploitation attempts; maintain privileged access monitoring (PAM) on all Hyper-V administrative activities; regularly audit and revoke unnecessary local administrative privileges.
Threat Intelligence Overview
NVD
CVE.org
EPSS
Exploit-DB
VulDB
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
A heap overflow occurs when a program writes data beyond the bounds of a buffer allocated in the heap memory region.
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GitHub PoC