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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DeliveryRepeatedly invoke racing Win32K syscalls
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ExploitWin kernel timing race window
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ExecutionCorrupt shared kernel object state
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PersistElevate to SYSTEM
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ImpactInstall persistence or move laterally
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V15 - Secure Coding and Architecture Concurrency control, locking
MITRE ATT&CK
1 technique across 1 tactic: 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 possess local, authenticated low-privileged code execution on the target (CVSS PR:L, AV:L) - this is a privilege-escalation primitive, not a remote entry point, and cannot be triggered over the network or by a remote unauthenticated actor. Success further depends on winning a race condition in Win32K (AC:H), meaning the attacker must repeatedly and precisely time concurrent operations to hit a non-deterministic window; there is no special product feature or non-default configuration that must be enabled, since Win32K is a core component present on all listed builds. Limiting factors that reduce realistic risk: the need for an existing local foothold, the timing-dependent unreliability of the race (SSVC Automatable 'no'), that no victim user interaction is involved (UI:N), and that the affected build must be below the fixed patch level listed by Microsoft. |
| Impact | The signals are internally consistent and point to a real-but-not-emergency local EoP. CVSS 7.0 with AV:L/AC:H/PR:L/UI:N/S:U and C:H/I:H/A:H means an attacker must already be running code as a low-privileged user and must win a timing-sensitive race (high complexity), but success yields full compromise. SSVC agrees: Exploitation 'none', Automatable 'no', but Technical Impact 'total' - the AC:H and non-automatable rating are the main things holding real-world urgency down. EPSS of 0.16% (5th percentile) reinforces low near-term exploitation probability, and the CVE is not on CISA KEV. This is a patch-in-normal-cycle item rather than a drop-everything issue, though the 'total' technical impact means it is valuable as a post-exploitation step in a chain and should not be deferred indefinitely, especially on multi-user or terminal-server hosts. |
| Exploit ScenarioDerived | An attacker who already has a low-privileged foothold - for example a standard user account, a compromised service, or code delivered via a separate phishing/RCE step - runs a program that repeatedly triggers the racing Win32K syscalls to hit the narrow timing window. On a successful race they corrupt kernel object state and escalate to SYSTEM, then use that access to disable defenses, install persistence, or move laterally. No public exploit is identified at time of analysis, and the high attack complexity means the attacker may need many attempts to win the race. |
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Alert meAnalysisAIv2 – Jul 15, 2026
Local privilege escalation in the Windows Win32K kernel-mode subsystem allows an already-authenticated attacker to win a race condition (CWE-362) and elevate to SYSTEM-level privileges across supported Windows 10, Windows 11, and Windows Server 2019-2025 builds. Reported by Microsoft with a vendor patch available; there is no public exploit identified at time of analysis and EPSS is low (0.16%, 5th percentile). CVSS 7.0 reflects high attack complexity (AC:H) driven by the timing-window nature of the flaw and the requirement for existing low-privilege access (PR:L).
Earlier versions of this analysis (1)
Local privilege escalation in the Windows Win32K kernel-mode subsystem lets a low-privileged authenticated user win a race condition to execute code with elevated (SYSTEM-level) privileges. The flaw affects a broad range of supported Windows client and server builds, from Windows 10 1809 through Windows 11 26H1 and Windows Server 2019 through 2025. Microsoft reported the issue and has shipped a fix; there is no public exploit identified at time of analysis and it is not listed in CISA KEV.
RemediationAI
Apply the Microsoft security update that raises each affected build past its fixed version: 10.0.17763.9020 (1809 / Server 2019), 10.0.19044.7548 (21H2), 10.0.19045.7548 (22H2), 10.0.20348.5386 (Server 2022), 10.0.26100.8875 (Windows 11 24H2), 10.0.26200.8875 (25H2), 10.0.28000.2525 (26H1), and 10.0.26100.33158 (Server 2025 and Server 2025 Server Core); these ship through the normal cumulative-update channel referenced at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54112. Because this is a Win32K kernel component with no configurable feature toggle, there is no clean product-level workaround, so patching is the only reliable fix. Until the update is deployed, reduce exposure by limiting who can execute code on the host - enforce least privilege, remove unnecessary interactive/local logon rights, and prioritize patching shared multi-user systems (RDS/terminal servers, jump boxes) where untrusted low-privileged users are most likely to be present; these controls limit the low-privileged foothold the exploit requires but do not remove the underlying flaw.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 20 packages in microsoft, euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Win32K (win32k.sys / win32kfull.sys) is the Windows kernel-mode graphics and windowing subsystem that services GDI and USER syscalls from user mode; it has a long history of local privilege-escalation bugs because it runs at kernel privilege yet is directly reachable from any interactive process. This issue is a CWE-362 race condition: two or more threads access a shared kernel resource without proper synchronization, so an attacker who carefully times concurrent operations can manipulate object state (for example a use-after-free or state-confusion window) that the kernel assumes is stable. The affected CPEs are Microsoft OS builds only - Windows 10 (1809, 21H2, 22H2), Windows 11 (24H2, 25H2, 26H1), and Windows Server 2019/2022/2025 including Server Core - confirming this is a core OS component rather than an optional feature.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Local low-privileged foothold required (AV:L/PR:L), timing-dependent race gives AC:H, and a successful win yields full SYSTEM compromise (C:H/I:H/A:H, scope unchanged).
Primary rating from Vendor (microsoft).
CVSS VectorNVD
Lifecycle Timeline
3DescriptionNVD
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Win32K allows an authorized attacker to elevate privileges locally.
Executive ViewAI
CVE-2026-54112 is a local privilege escalation vulnerability in the Windows kernel (Win32K subsystem) affecting Windows 10, Windows 11, and Windows Server 2019-2025, allowing already-authenticated users to escalate to SYSTEM-level privileges. This poses a significant risk to organizations where internal compromise is possible or where users may become compromised, potentially enabling complete system takeover. A vendor patch is available, making this a manageable risk for organizations with timely patching capabilities.
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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
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Race conditions occur when multiple concurrent requests exploit the brief time gap between checking a condition and acting upon it (TOCTOU - Time of Check, Time of Use).
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