Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessObtain low-privilege local access
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DeliveryInvoke USB print driver operation
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ExploitRace concurrent threads on shared resource
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ExecutionWin timing window to corrupt state
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ImpactExecute code as SYSTEM
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 local, authenticated access to the target (CVSS PR:L, AV:L) - the attacker must already be able to run code as a low-privileged user on the machine. The specific trigger is the Windows USB Print Driver code path, so the print/USB-print components must be present and reachable by the attacker's process. The dominant limiting factor is the race condition itself (AC:H): the attacker must reliably win a narrow timing window between concurrent threads accessing the shared resource, which is non-deterministic and typically needs repeated attempts; no user interaction is required (UI:N) and no network access is possible (local vector only). |
| Impact | The CVSS 3.1 vector (AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H, base 7.0 High) describes a local, low-privilege, high-complexity attack with full CIA impact - a classic local elevation-of-privilege profile. The AC:H and AV:L metrics are the key risk dampeners: an attacker must already have a foothold on the box and must reliably win a race condition, which is non-deterministic and typically requires many attempts. There is no CISA KEV listing and no public exploit identified, so this is not an active-exploitation emergency; however, USB print driver EoP bugs are attractive as sandbox-escape or post-compromise privilege chains, so it should be patched on the normal Patch Tuesday cadence rather than deferred. One data inconsistency to flag: the intelligence tags include 'Information Disclosure', but the description and CVSS (C:H/I:H/A:H) describe local privilege elevation - treat this as an EoP flaw and verify the exact impact against the Microsoft advisory. |
| Exploit ScenarioDerived | An attacker who already holds an ordinary user account or a low-privilege process on a Windows 11 24H2 or Windows Server 2025 host repeatedly triggers USB print driver operations while racing a second thread to hit the unsynchronized shared-resource window. On a successful race they corrupt privileged state and gain SYSTEM-level code execution, turning a limited foothold into full host control. No public proof-of-concept has been identified, and the high attack complexity means success typically requires many timing attempts. |
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Alert meAnalysisAIv1 – Jul 14, 2026
Local privilege escalation in the Windows USB Print Driver affects Windows 11 (24H2, 25H2, 26H1) and Windows Server 2025, where a race condition (improper synchronization of a shared resource) lets an already-authenticated local user win a timing window to execute code at elevated privilege. Reported by Microsoft with a patch available; no public exploit identified at time of analysis and it is not on CISA KEV. The high CVSS attack complexity (AC:H) reflects that the attacker must reliably win a narrow race, which tempers real-world exploitability.
RemediationAI
Apply the Microsoft security update for CVE-2026-49806 as documented in the MSRC advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49806 (Patch available per vendor advisory; exact fixed build not stated in the provided data, so pull the per-SKU KB from the advisory). Prioritize Windows 11 24H2/25H2/26H1 endpoints and Windows Server 2025 hosts, including Server Core. Where immediate patching is not possible, the practical compensating control for a USB-print EoP is to reduce local attack surface: restrict interactive and local logon to trusted administrators (the attacker needs PR:L local access), and on servers with no printing role disable or restrict the print/USB print components - with the trade-off that this breaks local and USB printer functionality for legitimate users. There is no network-facing control that mitigates this local-only flaw, so patching remains the durable fix.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 5 packages in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The flaw lives in the Windows USB print stack, the kernel-mode/driver components that service USB-attached printer devices. The root cause is CWE-362, a concurrent execution race condition: two or more threads access a shared resource without proper synchronization (locking/serialization), creating a time-of-check to time-of-use window an attacker can exploit to corrupt state or redirect a privileged operation. Per the CPE data the affected code ships in Windows 11 version 24H2, 25H2 and 26H1, plus Windows Server 2025 including Server Core installations, indicating this is current-branch Windows driver code rather than a legacy component.
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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-only race condition (AV:L, AC:H) exploitable by an existing low-privileged user (PR:L) with no user interaction, yielding full SYSTEM-level compromise (C:H/I:H/A:H).
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
DescriptionCVE.org
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows USB Print Driver allows an authorized attacker to elevate privileges locally.
Executive ViewAI
CVE-2026-49806 affects Windows 11 (24H2, 25H2, 26H1) and Windows Server 2025, enabling authenticated local users to escalate to system privileges through a race condition in the USB Print Driver. Organizations with these operating systems face elevated insider risk, particularly those with shared-access workstations or hybrid-work environments. A vendor patch is available and should be prioritized, though real-world exploitation risk is constrained by the requirement for local device access and precise technical execution timing.
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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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NVD
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