Vulnerability · Published Jun 9, 2026 · Assigned by microsoft
CVE-2026-45657Windows Kernel Remote Code Execution Vulnerability
Critical 9.8
In plain English
A critical-severity use-after-free in Windows 11 version 23H2 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 15.5% (higher than 97% of all known vulnerabilities).
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)15.5%top 3.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 – before 10.0.22631.7219 |
| Microsoft | Windows 11 Version 23H2 | 10.0.22631.0 – before 10.0.22631.7219 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 – before 10.0.26100.8655 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 – before 10.0.26200.8655 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 – before 10.0.28000.2269 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – before 10.0.20348.5256 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.32995 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.32995 |
Weakness: CWE-416, CWE-122 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
References
- Windows Kernel Remote Code Execution Vulnerability vendor-advisory, patch