CVE-2026-65681: Windows iSCSI Target Service Denial of Service Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-11 · updated 2026-10-30
Weakness: CWE-476

Description

Null pointer dereference in Windows iSCSI Target Service allows an unauthorized attacker to deny service over a network.

Affected products

Microsoft Windows 10 1607: before 10.0.14393.9418 — fixed in 10.0.14393.9418
Microsoft Windows 10: before 10.0.17763.9115 — fixed in 10.0.17763.9115
Microsoft Windows Server 2016: before 10.0.14393.9418 — fixed in 10.0.14393.9418
Microsoft Windows Server 2019: before 10.0.17763.9115 — fixed in 10.0.17763.9115
Microsoft Windows Server 2022: before 10.0.20348.5440 — fixed in 10.0.20348.5440
Microsoft Windows Server 2025: before 10.0.26100.33222 — fixed in 10.0.26100.33222
Microsoft Windows 10 1607: from 10.0.14393.0 before 10.0.14393.9418 — fixed in 10.0.14393.9418
Microsoft Windows 10: from 10.0.17763.0 before 10.0.17763.9121 — fixed in 10.0.17763.9121
Microsoft Windows Server 2016: from 10.0.14393.0 before 10.0.14393.9418 — fixed in 10.0.14393.9418
Microsoft Windows Server 2019: from 10.0.17763.0 before 10.0.17763.9121 — fixed in 10.0.17763.9121
Microsoft Windows Server 2022: from 10.0.20348.0 before 10.0.20348.5499 — fixed in 10.0.20348.5499
Microsoft Windows Server 2025: from 10.0.26100.0 before 10.0.26100.33296 — fixed in 10.0.26100.33296

How to fix

Upgrade to a fixed version: Microsoft Windows 10 1607 10.0.14393.9418; Microsoft Windows 10 10.0.17763.9115; Microsoft Windows Server 2016 10.0.14393.9418; Microsoft Windows Server 2019 10.0.17763.9115; Microsoft Windows Server 2022 10.0.20348.5440; Microsoft Windows Server 2025 10.0.26100.33222; Microsoft Windows 10 1607 10.0.14393.9418; Microsoft Windows 10 10.0.17763.9121; Microsoft Windows Server 2016 10.0.14393.9418; Microsoft Windows Server 2019 10.0.17763.9121; Microsoft Windows Server 2022 10.0.20348.5499; Microsoft Windows Server 2025 10.0.26100.33296. Check the vendor advisory for mitigations.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-65681

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