Security Resilience

CVE-2023-21547

Memory Safety in Microsoft Windows 10 1809

Published
10 January 2023
Modified
21 November 2024
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 0.89 99.8th percentile
Risk Priority 83 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-21547 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Microsoft Windows 10 1809. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Credential Dumping (T1003); ranked in the top 0.2% 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-2023-21547 is a denial-of-service vulnerability in the Internet Key Exchange (IKE) protocol implementation, carrying a CVSS 3.1 score of 7.5. The flaw is associated with CWE-476 and CWE-400 and permits remote, unauthenticated attackers to trigger crashes or resource exhaustion that render affected systems unavailable.

An attacker with network access can send specially crafted IKE traffic to exploit the issue, achieving denial of service without any user interaction or elevated privileges. The attack requires no authentication and targets the availability of the IKE service directly.

Microsoft’s security advisory at msrc.microsoft.com details the affected components and supplies patches; administrators should apply the updates referenced in the guidance to eliminate the exposure.

EPSS for the CVE rose from a low baseline to a recorded peak of 0.0685 on 2025-12-11 before receding to the current value of 0.0444, indicating a measurable increase in exploitation interest after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Internet Key Exchange (IKE) Protocol Denial of Service Vulnerability

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
T1003.007 Proc Filesystem Credential Access
Adversaries may gather credentials from the proc filesystem or `/proc`.
T1006 Direct Volume Access Stealth
Adversaries may directly access a volume to bypass file access controls and file system monitoring.
T1011 Exfiltration Over Other Network Medium Exfiltration
Adversaries may attempt to exfiltrate data over a different network medium than the command and control channel.
T1012 Query Registry Discovery
Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software.
T1016 System Network Configuration Discovery Discovery
Adversaries may look for details about the network configuration and settings, such as IP and/or MAC addresses, of systems they access or through information discovery of remote systems.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20661Same product: Microsoft Windows 10 1607
CVE-2023-32008Same product: Microsoft Windows 10 1607
CVE-2023-36709Same product: Microsoft Windows 10 1809
CVE-2023-24938Same product: Microsoft Windows 10 1809
CVE-2023-36603Same product: Microsoft Windows 10 1809
CVE-2023-24859Same product: Microsoft Windows 10 1607
CVE-2023-35338Same product: Microsoft Windows 10 1607
CVE-2023-21683Same product: Microsoft Windows 10 1607
CVE-2024-26183Same product: Microsoft Windows 10 1607
CVE-2023-24940Same product: Microsoft Windows 10 1607

Affected Assets

microsoft
windows 10 1607
all versions
microsoft
windows 10 1809
all versions
microsoft
windows 10 21h2
all versions
microsoft
windows 10 22h2
all versions
microsoft
windows 11 21h2
all versions
microsoft
windows 11 22h2
all versions
microsoft
windows server 2016
all versions
microsoft
windows server 2019
all versions
microsoft
windows server 2022
all versions

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-400

Limiting concurrent sessions directly prevents uncontrolled resource consumption by capping the number of active sessions per user or account.

addresses: CWE-400

Analysis identifies uncontrolled resource consumption indicative of denial-of-service or abuse attempts.

addresses: CWE-400

Contingency plan testing includes resource exhaustion scenarios to verify recovery, making it harder for attackers to sustain exploits that cause uncontrolled consumption.

addresses: CWE-400

Updated contingency plans include current procedures to detect, contain, and recover from resource exhaustion, limiting an attacker's ability to sustain impact from uncontrolled consumption.

addresses: CWE-400

Alternate site allows resumption of operations if resource exhaustion at the primary site is exploited to cause unavailability.

addresses: CWE-400

Alternate telecommunications services enable resumption of essential functions when primary services become unavailable due to uncontrolled resource consumption.

addresses: CWE-400

The team can analyze and respond to resource exhaustion incidents, reducing the impact of attacks that exploit uncontrolled consumption weaknesses.

addresses: CWE-400

Timely maintenance support and spare parts enable rapid recovery from failures induced by uncontrolled resource consumption, shortening the impact window of denial-of-service attacks.

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 partial match
blocks

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.

removes
removes
removes
removes
finds

Pre-agreed severity-based prioritization and resource allocation during incident triage reduce the likelihood that an attacker-induced resource exhaustion will overwhelm the organization before corrective action is taken.

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-400, a class-level weakness. Rules are authored against its narrower children: CWE-770.

References