Cyber Resilience

CVE-2023-21700

Memory Safety in Microsoft Windows Server 2008 r2

Published
14 February 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.017 74th percentile
Risk Priority 72 floored blend · peak EPSS

Summary

CVE-2023-21700 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked in the top 26% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2023-21700 is a denial-of-service vulnerability in the Windows iSCSI Discovery Service, assigned a CVSS 3.1 base score of 7.5 with the vector AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H and linked to CWE-476. The flaw permits remote attackers to disrupt the service without authentication or user interaction.

An unauthenticated network attacker can send crafted requests that trigger the vulnerability, resulting in high-impact loss of availability for the affected iSCSI component while leaving confidentiality and integrity unaffected.

Microsoft published an advisory for CVE-2023-21700 that describes the issue and supplies remediation guidance; the advisory is available at the Microsoft Security Response Center link referenced in the CVE record.

The associated EPSS score reached a peak of 0.2664 with no subsequent material increase from that level.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Windows iSCSI Discovery Service Denial of Service Vulnerability

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

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CVE-2023-24940Same product: Microsoft Windows 10 1607
CVE-2023-35338Same product: Microsoft Windows 10 1607
CVE-2023-24910Same product: Microsoft Windows 10 1607
CVE-2024-26183Same product: Microsoft Windows 10 1607
CVE-2023-21683Same product: Microsoft Windows 10 1607
CVE-2024-21356Same product: Microsoft Windows 10 1607
CVE-2023-36602Same product: Microsoft Windows 10 1607
CVE-2024-43520Same product: Microsoft Windows 10 1607
CVE-2023-32008Same product: Microsoft Windows 10 1607

Affected Assets

microsoft
windows 10
≤ 10.0.10240.19747
microsoft
windows 10 1607
≤ 10.0.14393.5717
microsoft
windows 10 1809
≤ 10.0.17763.4010
microsoft
windows 10 20h2
≤ 10.0.19042.2604
microsoft
windows 10 21h2
≤ 10.0.19044.2604
microsoft
windows 10 22h2
≤ 10.0.19045.2604
microsoft
windows 11 21h2
≤ 10.0.22000.1574
microsoft
windows 11 22h2
≤ 10.0.22621.1265
microsoft
windows server 2008
all versions, r2
microsoft
windows server 2012
all versions, r2
+3 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References