CVE-2023-33163: Windows Network Load Balancing Remote Code Execution Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-07-11 · updated 2026-06-17
Weakness: CWE-591

Description

Windows Network Load Balancing Remote Code Execution Vulnerability

Affected products

Microsoft Windows Server 2008: r2-sp1
Microsoft Windows Server 2012: r2
Microsoft Windows Server 2016: all versions
Microsoft Windows Server 2019: all versions
Microsoft Windows Server 2022: all versions
Microsoft Windows Server 2008 R2 Service Pack 1: from 6.1.7601.0 before 6.1.7601.26623 — fixed in 6.1.7601.26623
Microsoft Windows Server 2012: from 6.2.9200.0 before 6.2.9200.24374 — fixed in 6.2.9200.24374
Microsoft Windows Server 2012 R2: from 6.3.9600.0 before 6.3.9600.21063 — fixed in 6.3.9600.21063
Microsoft Windows Server 2016: from 10.0.14393.0 before 10.0.14393.6085 — fixed in 10.0.14393.6085
Microsoft Windows Server 2019: from 10.0.17763.0 before 10.0.17763.4645 — fixed in 10.0.17763.4645
Microsoft Windows Server 2022: from 10.0.20348.0 before 10.0.20348.1850 — fixed in 10.0.20348.1850

How to fix

Upgrade to a fixed version: Microsoft Windows Server 2008 R2 Service Pack 1 6.1.7601.26623; Microsoft Windows Server 2012 6.2.9200.24374; Microsoft Windows Server 2012 R2 6.3.9600.21063; Microsoft Windows Server 2016 10.0.14393.6085; Microsoft Windows Server 2019 10.0.17763.4645; Microsoft Windows Server 2022 10.0.20348.1850. Check the vendor advisory for mitigations.

References

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