CVE-2026-83789: Windows SMB Client Elevation of Privilege Vulnerability
Heap-based buffer overflow in Windows SMB Client allows an unauthorized attacker to elevate privileges over a network.
Other sources
Windows SMB Client Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.14393.9612Patch KB5126868 - Upgrade
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Fixed in 10.0.28000.3231Patch KB5127646 - Upgrade
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Fixed in 10.0.26300.9711Patch KB5127648 - Upgrade
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Fixed in 10.0.17763.9376Patch KB5126651 - Upgrade
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Fixed in 10.0.19044.7807Patch KB5126657 - Upgrade
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Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
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Fixed in 6.2.9200.26434Patch KB5126835 - Upgrade
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Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
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Fixed in 10.0.26100.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7652Patch KB5126653 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5761Patch KB5126655
Event History
Frequently Asked Questions
Does exploitation require the attacker to authenticate first?
No. The vulnerability is rated PR:N, indicating no privileges are required before exploitation.
Is user interaction required for exploitation?
Yes. The CVSS vector includes UI:R, so exploitation requires user interaction. The supplied data does not specify what form that interaction takes.
Which Windows products are listed as affected?
The listed affected products are Windows 10, Windows 11, and Windows Server 2012, 2012 R2, 2016, 2019, 2022, and 2025.