CVE-2026-83834Windows 11 Version 26h2 For Arm64-Based Systems Use-After-Free
Use after free in Windows Kernel-Mode Drivers allows an authorized attacker to elevate privileges locally.
Published Oct 13, 2026 · Updated Oct 18, 2026 · Also known as EUVD-2026-99377, GHSA-m3qw-3v2g-89wc
Key Facts
Patch in the next maintenance window- CVE-2026-83834 is a high-severity vulnerability (CVSS 7.0 v3.1) affecting Windows 11 Version 26h2 For Arm64-Based Systems (Microsoft), Windows 11 Version 26h2 For X64-Based Systems (Microsoft), Windows 10 1607 (Microsoft) and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 0.2% probability of exploitation in the next 30 days.
- Fixed versions are available, including Windows 10 Version 1607 10.0.14393.9612, Windows 10 Version 1607 for 32-bit Systems 10.0.14393.9612, Windows 10 Version 1809 10.0.17763.9376.
- Brandefense priority: patch in the next maintenance window, because of its high severity, although no exploitation is known.
Scores
CVSS v3.1
7.0
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
EPSS (30-day exploit likelihood)
0.2%
Higher than 9.8% of all scored CVEs
Exploit maturity
Proof of concept
ATLAS score
42/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Proof of concept
Public exploit code
1
Proof-of-concept links
In-the-wild evidence
0
Reports of active use
Description
Use after free in Windows Kernel-Mode Drivers allows an authorized attacker to elevate privileges locally.
Affected Products
56 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Windows 11 Version 26h2 For Arm64-Based SystemsMicrosoft | See advisory | 10.0.26300.9711 |
| Windows 11 Version 26h2 For X64-Based SystemsMicrosoft | See advisory | n/a |
| Windows 10 1607Microsoft | See advisory | 10.0.14393.9612 |
| Windows 10 1809Microsoft | See advisory | 10.0.17763.9376 |
| windows 10 21H2Microsoft | See advisory | 10.0.19044.7807 |
Patched Releases
Windows 10 Version 1607
10.0.14393.9612
Windows 10 Version 1607 for 32-bit Systems
10.0.14393.9612
Windows 10 Version 1809
10.0.17763.9376
Windows 10 Version 1809 for 32-bit Systems
10.0.17763.9376
Windows 10 Version 21H2
10.0.19044.7807
Windows 10 Version 21H2 for 32-bit Systems
10.0.19044.7807
Windows 10 Version 22H2
10.0.19044.7807, 10.0.19045.7807
Windows 10 Version 22H2 for x64-based Systems
10.0.19044.7807, 10.0.19045.7807
Windows 11 Version 23H2
10.0.22631.7652
Windows 11 Version 23H2 for ARM64-based Systems
10.0.22631.7652
Windows 11 Version 23H2 for x64-based Systems
10.0.22631.7652
Windows 11 Version 24H2
10.0.26100.9711
Windows 11 Version 24H2 for ARM64-based Systems
10.0.26100.9711
Windows 11 Version 25H2
10.0.26200.9711
Windows 11 Version 25H2 for ARM64-based Systems
10.0.26200.9711
Windows 11 version 26H1
10.0.28000.3231
Windows 11 version 26H1 for x64-based Systems
10.0.28000.3231
Windows 11 Version 26H2
10.0.26300.9711
Windows 11 Version 26h2 For Arm64-Based Systems
10.0.26300.9711
Windows Server 2016
10.0.14393.9612
Windows Server 2016 (Server Core installation)
10.0.14393.9612
Windows Server 2019
10.0.17763.9376
Windows Server 2019 (Server Core installation)
10.0.17763.9376
Windows Server 2022
10.0.20348.5761
Windows Server 2025
10.0.26100.33650
Timeline
Publicly disclosed
Oct 13, 2026
Last updated
Oct 18, 2026
Weakness Type
- CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
- CWE-416 Use After Free
FAQ
Common Questions.
Use after free in Windows Kernel-Mode Drivers allows an authorized attacker to elevate privileges locally.
Affected: Windows 11 Version 26h2 For Arm64-Based Systems (Microsoft); Windows 11 Version 26h2 For X64-Based Systems (Microsoft); Windows 10 1607 (Microsoft), among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Windows 10 Version 1607 10.0.14393.9612, Windows 10 Version 1607 for 32-bit Systems 10.0.14393.9612, Windows 10 Version 1809 10.0.17763.9376.
Brandefense priority: patch in the next maintenance window, because of its high severity, although no exploitation is known.
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