Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessObtain low-privileged local code execution
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DeliveryInvoke crafted Win32K syscalls
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ExploitTrigger use-after-free of freed kernel object
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ExecutionReclaim and corrupt kernel memory
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ImpactExecute code as SYSTEM
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Memory lifecycle management
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Privilege Escalation The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires the attacker to already have local, authenticated access with at least low privileges on the target Windows system (PR:L) and the ability to execute arbitrary code that issues Win32K syscalls - there is no remote network vector (AV:L) and no user interaction by a victim is needed (UI:N). The limiting factor is the need for a pre-existing foothold: this is a second-stage privilege-escalation primitive, not an initial-access flaw, so it cannot be triggered by an unauthenticated remote attacker. Affected deployments are unpatched builds across Windows 10 (1809/21H2/22H2), Windows 11 (23H2 through 26H2), and Windows Server 2019/2022/2025 below the fixed build numbers listed in the EUVD data; applying the vendor update removes the condition. |
| Impact | This is a genuine but not emergency-grade priority. The CVSS 3.1 vector (AV:L/AC:L/PR:L/UI:N) describes a local-only, low-complexity attack requiring an already-authenticated low-privileged user, yielding total compromise (C:H/I:H/A:H) - consistent with a classic Win32K kernel elevation-of-privilege primitive used in post-compromise chains. The signals are internally consistent rather than conflicting: CISA's SSVC framework reports Exploitation=none and Automatable=no, which agrees with the absence of any KEV listing and no identified public POC, indicating no observed in-the-wild use. SSVC Technical Impact=total aligns with the C/I/A=High kernel impact. No EPSS score was provided in the input, so probabilistic exploitation likelihood cannot be quantified here. Net assessment: a credible, patch-soon kernel EoP (attackers typically weaponize Win32K UAFs as the second stage after initial code execution), but with no evidence of active or automatable exploitation it does not warrant drop-everything emergency response - standard Patch Tuesday remediation cadence is appropriate. |
| Exploit ScenarioDerived | An attacker who has already achieved low-privileged code execution on a Windows host (e.g., via phishing or a compromised standard user account) runs a crafted program that triggers the use-after-free in the Win32K kernel component to corrupt kernel memory and elevate to SYSTEM. No public exploit code has been identified at time of analysis, and the low attack complexity means a working exploit would be reliable once developed. User interaction is not required beyond the attacker executing their own code locally. |
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Alert meAnalysisAIv1 – Oct 14, 2026
Local privilege escalation in Windows Win32K allows an attacker who already holds low-privileged, authenticated local access to trigger a use-after-free in the kernel-mode window manager driver and obtain SYSTEM-level code execution, with high impact to confidentiality, integrity, and availability. The defect is a second-stage primitive rather than an initial-access flaw: the assessed vector (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) requires a pre-existing foothold on the host plus the ability to execute code issuing Win32K syscalls, and it cannot be reached by an unauthenticated remote attacker. No public exploit code has been identified at time of analysis, CISA's SSVC data records exploitation as "none" and automatable as "no", and Microsoft has released a vendor patch covering all listed Windows client and server builds.
RemediationAI
Apply the Microsoft security update referenced by the MSRC advisory https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83762 - the vendor-released patch brings affected builds to Windows 11 23H2 10.0.22631.7652, 24H2 10.0.26100.9711, 25H2 10.0.26200.9711, 26H1 10.0.28000.3231, or 26H2 10.0.26300.9711; Windows 10 1809 10.0.17763.9376, 21H2/22H2 10.0.19044.7807; Windows Server 2019 10.0.17763.9376, Server 2022 10.0.20348.5761, and Server 2025 10.0.26100.33650. Deploy through Windows Update, WSUS/Configuration Manager, or the Microsoft Update Catalog, and plan for a reboot since win32k changes require it; prioritize internet-facing and multi-user endpoints first because the flaw is a post-compromise escalation primitive that only becomes dangerous after an attacker already has local code execution. Where immediate patching is not possible, the most effective compensating control is to shrink the pre-existing foothold the exploit depends on: remove or tightly restrict interactive local logon rights for non-administrative users, enforce least-privilege and application allowlisting so untrusted code cannot run and issue Win32K syscalls, and monitor for unexpected SYSTEM-level process creation or kernel crashes that may indicate exploitation attempts - the trade-off is reduced user flexibility and additional operational overhead in defining allowlists. On Windows Server, deploying or migrating to Server Core reduces the graphical attack surface but sacrifices GUI management tools and some third-party agents; disabling Win32K entirely is not viable on Desktop Experience systems because it breaks the window manager and user-object subsystem. Microsoft's advisory and the EUVD/NVD cross-references should be monitored for any update to exploitability status.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 13 packages in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Win32K is the kernel-mode subsystem that implements the Windows graphics device interface, window manager, and user-object handling, exposed to local processes through a well-known syscall surface (win32k.sys / win32kfull.sys). CVE-2026-83762 is a CWE-416 use-after-free: a kernel object is freed by one operation but can still be referenced or reallocated by another, leaving dangling pointers that an attacker can shape into controlled kernel memory corruption. Because the component runs at ring 0, successful heap grooming and reuse can yield arbitrary code execution in kernel context, escalation to SYSTEM, or a bugcheck (reflected in the associated Denial Of Service and Memory Corruption tags). The CVSS vector confirms the practical prerequisites - AV:L and PR:L mean the attacker must already run code locally, UI:N means no victim interaction is needed, and the unchanged scope with C:H/I:H/A:H indicates total impact once the primitive is exercised. CISA's SSVC assessment rates technical impact as "total" while noting exploitation is not observed and the flaw is not easily automatable, which is consistent with a manually crafted, post-compromise escalation rather than a wormable or mass-exploited issue.
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Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Local kernel EoP requiring existing low-privileged code execution gives AV:L and PR:L; the use-after-free is directly triggerable so AC:L, and kernel SYSTEM compromise yields C/I/A:H.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
2DescriptionCVE.org
Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.
Executive ViewAI
Microsoft Windows client and server builds are affected by a high-severity local privilege escalation vulnerability (CVE-2026-83762) in the Win32K driver, which could allow an authenticated attacker with existing low-privileged access to gain SYSTEM-level control. No public exploit identified at time of analysis, and active exploitation has not been observed, but successful exploitation could lead to full compromise of confidentiality, integrity, and availability. Patch available per vendor advisory; organizations should prioritize applying it to prevent potential escalation from an initial foothold.
Apply vendor patch.
Threat Intelligence Overview
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
Use-after-free vulnerabilities occur when a program continues to access memory through a pointer after that memory has been deallocated.
Memory corruption occurs when a program writes data beyond the boundaries of allocated memory regions or accesses memory in unintended ways, violating the integrity of the process's address space.
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
EUVD-2026-99983
GHSA-8vfg-365m-x964
NVD
CVE.org
EPSS
Vulnrichment
Exploit-DB