CVE-2026-83721
published 2026-10-13CVE-2026-83721: Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.
PriorityP347high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.32%
23.5th percentile
Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_11_version_24h2 | >= 10.0.26100.0 < 10.0.26100.9711 | 10.0.26100.9711 |
| microsoft | windows_11_version_25h2 | >= 10.0.26200.0 < 10.0.26200.9711 | 10.0.26200.9711 |
| microsoft | windows_11_version_26h1 | >= 10.0.28000.0 < 10.0.28000.3231 | 10.0.28000.3231 |
| microsoft | windows_11_version_26h2 | >= 10.0.26300.0 < 10.0.26300.9711 | 10.0.26300.9711 |
| microsoft | windows_server_2025 | >= 10.0.26100.0 < 10.0.26100.33650 | 10.0.26100.33650 |
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VulDB
Microsoft Windows up to Server 2025 Win32k use after free
vuldb·2026-10-14·CVSS 7.8
CVE-2026-83721 [HIGH] Microsoft Windows up to Server 2025 Win32k use after free
A vulnerability classified as very critical has been found in Microsoft Windows 11 24H2/11 25H2/11 26H1/11 26H2/Server 2025. Impacted is an unknown function of the component Win32k. The manipulation leads to use after free.
This vulnerability is uniquely identified as CVE-2026-83721. Local access is required to approach this attack. No exploit exists.
To fix this issue, it is recommended to deploy a patch.
GHSA
Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.
ghsa_unreviewed·2026-10-13
CVE-2026-83721 [HIGH] CWE-416 Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.
Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.
No detection rules found.
No public exploits indexed.
Sans Isc
October 2026 Microsoft Patch Tuesday, (Tue, Oct 13th)
blogs_sans_isc·2026-10-13·CVSS 8.8
CVE-2026-96951 [HIGH] October 2026 Microsoft Patch Tuesday, (Tue, Oct 13th)
October 2026 Microsoft Patch Tuesday
Published: 2026-10-13. Last Updated: 2026-10-13 19:25:52 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)
Microsoft today released patches for 1,417 vulnerabilities. 76 of these vulnerabilities are rated critical, with 7 critical vulnerabiilties requiring no customer actions. One vulnerability was disclosed before today's patch Tuesday, and one is already exploited.
CVE-2026-96951: An already exploited Windows Shell Security Feature Bypass Vulnerability. This vulnerabliity allows bypassing the "Mark of the Web" making it easier to exeucte code by sending a malicious message to a user via e-mail or instant messaging. The victim will still have to open the file.
CVE-2026-108398: This vulnerability, a .NET framework security feature bypass, could be
Rapid7
Patch Tuesday - October 2026
blogs_rapid7·2026-10-13·CVSS 8.8
CVE-2026-96951 [HIGH] Patch Tuesday - October 2026
Microsoft is publishing 1,413 own-product vulnerabilities on October 2026 Patch Tuesday , including 1,102 vulnerabilities in Windows. Anyone who enjoyed last month’s record-setting Patch Tuesday will love the October 2026 edition, because it’s much bigger still. As Rapid7 has noted over the course of 2026, there is every reason to suppose that vulnerability volumes will continue to rise. Microsoft is aware of exploitation in the wild for just one of the vulnerabilities published today, as well as public disclosure for two others.
## Windows Shell: zero-day security feature bypass
The Windows Shell is Microsoft’s term for the GUI interaction logic for the entire OS provided by explorer.exe and associated libraries and APIs, and for the second time this year , the Windows Shell is the site
2026-10-13
Published