CVE-2026-83789: Windows SMB Client Elevation of Privilege Vulnerability
Published Oct 13, 2026
·Updated
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
59 affected componentsFixes available
Microsoft Windows SMB Client
Microsoft Windows Server 2016<10.0.14393.9612
10.0.14393.9612
Microsoft Windows Server 2019<10.0.17763.9376
10.0.17763.9376
Microsoft Windows Server 2025<10.0.26100.33650
10.0.26100.33650
Microsoft Windows Server 2012<6.2.9200.26434
6.2.9200.26434
Microsoft Windows Server 2012 R2<6.3.9600.23470
6.3.9600.23470
Microsoft Windows Server 2012<6.2.9200.26434
6.2.9200.26434
Microsoft Windows Server 2016<10.0.14393.9612
10.0.14393.9612
Microsoft Windows Server 2012 R2<6.3.9600.23470
6.3.9600.23470
Microsoft Windows Server 2025<10.0.26100.33650
10.0.26100.33650
Microsoft Windows Server 2022<10.0.20348.5761
10.0.20348.5761
Microsoft Windows Server 2022<10.0.20348.5761
10.0.20348.5761
Microsoft Windows Server 2019<10.0.17763.9376
10.0.17763.9376
Microsoft Windows 10 1607<10.0.14393.9612
Microsoft Windows 10 1607<10.0.14393.9612
Microsoft Windows 10 1809<10.0.17763.9376
Microsoft Windows 10 1809<10.0.17763.9376
Microsoft Windows 10 21h2<10.0.19044.7807
Microsoft Windows 10 21h2<10.0.19044.7807
Microsoft Windows 10 21h2<10.0.19044.7807
Microsoft Windows 10 22h2<10.0.19045.7807
Microsoft Windows 10 22h2<10.0.19045.7807
Microsoft Windows 10 22h2<10.0.19045.7807
Microsoft Windows 11 23h2<10.0.22631.7652
Microsoft Windows 11 23h2<10.0.22631.7652
Microsoft Windows 11 24h2<10.0.26100.9711
Microsoft Windows 11 24h2<10.0.26100.9711
Microsoft Windows 11 25h2<10.0.26200.9711
Microsoft Windows 11 25h2<10.0.26200.9711
Microsoft Windows 11 26h1<10.0.28000.3231
Microsoft Windows 11 26h1<10.0.28000.3231
Microsoft Windows 11 26h2<10.0.26300.9711
Microsoft Windows 11 26h2<10.0.26300.9711
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016<10.0.14393.9612
Microsoft Windows Server 2019<10.0.17763.9376
Microsoft Windows Server 2022<10.0.20348.5761
Microsoft Windows Server 2025<10.0.26100.33650
Microsoft Windows 10=21H2, >=10.0.19044<10.0.19044.7807
10.0.19044.7807
Microsoft Windows 11=26H2, >=10.0.26300<10.0.26300.9711
10.0.26300.9711
Microsoft Windows 10=1607, >=10.0.14393<10.0.14393.9612
10.0.14393.9612
Microsoft Windows 11=26H2, >=10.0.26300<10.0.26300.9711
10.0.26300.9711
Microsoft Windows 10=21H2, >=10.0.19044<10.0.19044.7807
10.0.19044.7807
Microsoft Windows 11=26H1, >=10.0.28000<10.0.28000.3231
10.0.28000.3231
Microsoft Windows 11=26H1, >=10.0.28000<10.0.28000.3231
10.0.28000.3231
Microsoft Windows 10=1607, >=10.0.14393<10.0.14393.9612
10.0.14393.9612
Microsoft Windows 11=24H2, >=10.0.26100<10.0.26100.9711
10.0.26100.9711
Microsoft Windows 11=24H2, >=10.0.26100<10.0.26100.9711
10.0.26100.9711
Microsoft Windows 11=23H2, >=10.0.22631<10.0.22631.7652
10.0.22631.7652
Microsoft Windows 11=25H2, >=10.0.26200<10.0.26200.9711
10.0.26200.9711
Microsoft Windows 11=23H2, >=10.0.22631<10.0.22631.7652
10.0.22631.7652
Microsoft Windows 11=25H2, >=10.0.26200<10.0.26200.9711
10.0.26200.9711
Microsoft Windows 10=22H2, >=10.0.19045<10.0.19045.7807
10.0.19045.7807
Microsoft Windows 10=22H2, >=10.0.19045<10.0.19045.7807
10.0.19045.7807
Microsoft Windows 10=21H2, >=10.0.19044<10.0.19044.7807
10.0.19044.7807
Microsoft Windows 10=1809, >=10.0.17763<10.0.17763.9376
10.0.17763.9376
Microsoft Windows 10=22H2, >=10.0.19045<10.0.19045.7807
10.0.19045.7807
Microsoft Windows 10=1809, >=10.0.17763<10.0.17763.9376
10.0.17763.9376
Remediation
Event History
Oct 13, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
CVE Published
via MITRE·07:00 PM
Data Sourced
via MITRE·07:00 PM
DescriptionSeverity
Data Sourced
via NVD·07:20 PM
RemedyDescriptionSeverityWeaknessAffected Software
Frequently Asked Questions
1
Does exploitation require the attacker to authenticate first?
No. The vulnerability is rated PR:N, indicating no privileges are required before exploitation.
2
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.
3
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.