CVE & CISA-KEV Catalog

CVE-2023-21811

HIGHEPSS 74th pctl
7.5
CVSS v3
NVD

Description

Windows iSCSI Service Denial of Service Vulnerability

How to fix

Remediation Available
Windows 10Windows
Install:KB5022858Microsoft
Windows 10 Version 1607Windows
Install:KB5022838Microsoft
Windows 10 Version 1809Windows
Install:KB5022840Microsoft
Windows 10 Version 20H2Windows
Install:KB5022834Microsoft
Windows 10 Version 21H2Windows
Install:KB5022834Microsoft
Windows 10 Version 22H2Windows
Install:KB5022834Microsoft
Windows 11 Version 22H2Windows
Install:KB5022845Microsoft
Windows 11 version 21H2Windows
Install:KB5022836Microsoft
Windows Server 2008Windows
Install:KB5022893Microsoft
Install:KB5022890Microsoft
Windows Server 2008 R2Windows
Install:KB5022872Microsoft
Install:KB5022874Microsoft
Windows Server 2012Windows
Install:KB5022903Microsoft
Install:KB5022895Microsoft
Windows Server 2012 (Server Core installation)Windows
Install:KB5022903Microsoft
Install:KB5022895Microsoft
Windows Server 2012 R2Windows
Install:KB5022894Microsoft
Install:KB5022899Microsoft
Windows Server 2012 R2 (Server Core installation)Windows
Install:KB5022894Microsoft
Install:KB5022899Microsoft
Windows Server 2016Windows
Install:KB5022838Microsoft
Windows Server 2016 (Server Core installation)Windows
Install:KB5022838Microsoft
Windows Server 2019Windows
Install:KB5022840Microsoft
Windows Server 2019 (Server Core installation)Windows
Install:KB5022840Microsoft
Windows Server 2022Windows
Install:KB5022921
Install:KB5022842Microsoft
Windows Server 2022 (Server Core installation)Windows
Install:KB5022921
Install:KB5022842Microsoft

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityNone
AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

1.65%probability of exploitation in 30 days
74thpercentile

Elevated risk: more likely to be exploited than 74% of all known CVEs.

References

Related Vulnerabilities

Other CWE-126 (Buffer Over-read) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2023-49285High8.689%-Fix
CVE-2017-7668High7.557%-Fix
CVE-2017-7679Critical9.839%-Fix
CVE-2025-21277High7.538%-Fix
CVE-2024-38071High7.536%-Fix
CVE-2009-2495Medium6.534%--

Common questions

How do I fix CVE-2023-21811?

Published advisories record a fix for 20 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2023-21811 being actively exploited?

Not that we know of. CVE-2023-21811 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 1.7% is the estimated probability that it will be exploited in the next 30 days. That is higher than 74% of all scored CVEs.

How severe is CVE-2023-21811?

CVE-2023-21811 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2023-21811 affect?

Published advisories record a fix for Windows 10 (Windows), Windows 10 Version 1607 (Windows), Windows 10 Version 1809 (Windows), Windows 10 Version 20H2 (Windows), and 16 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2023-21811
CVE-2023-21811 severity badge

Markdown

[![CVE-2023-21811](https://tridentstack.com/cve/badge/CVE-2023-21811.svg)](https://tridentstack.com/cve/CVE-2023-21811)

HTML

<a href="https://tridentstack.com/cve/CVE-2023-21811"><img src="https://tridentstack.com/cve/badge/CVE-2023-21811.svg" alt="CVE-2023-21811"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it worksStart freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.