Security Resilience

CVE-2023-21819

Memory Safety in Microsoft Windows 10 1809 ≤ 10.0.17763.4010

Memory Safety
Published
14 February 2023
Modified
19 August 2026
Patch / advisory
View 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 0.31 98th percentile
Risk Priority 75 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-2023-21819 is a high-severity Out-of-bounds Read (CWE-125) vulnerability in Microsoft Windows 10 1809. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 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-2023-21819 is a denial of service vulnerability affecting the Windows Secure Channel component. It received a CVSS 3.1 score of 7.5 reflecting network attackability with low complexity, no privileges or user interaction required, and high impact solely on availability, along with association to CWE-125.

An unauthenticated remote attacker can send crafted network traffic to trigger the flaw and disrupt service availability in the Secure Channel implementation.

Microsoft has published an advisory entry for CVE-2023-21819 that security practitioners can reference for patch and mitigation details.

The EPSS score rose from a low baseline to a peak of 0.3919 before receding to the current value of 0.2138, indicating a period of elevated exploitation interest after disclosure.

EU & UK References

Vulnerability Data

Windows Secure Channel Denial of Service Vulnerability

CWE(s)
CWE-125NVD-CWE-noinfo

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control
Adversaries may obfuscate command and control traffic to make it more difficult to detect.
attack.mitre.org →
T1001.002 Steganography Command And Control
Adversaries may use steganographic techniques to hide command and control traffic to make detection efforts more difficult.
attack.mitre.org →
T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
attack.mitre.org →
T1003.003 NTDS Credential Access
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.006 DCSync Credential Access
Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-21539Same product: Microsoft Windows 10 20H2
CVE-2023-35358Same product: Microsoft Windows 10 1809
CVE-2023-35357Same product: Microsoft Windows 10 1809
CVE-2024-26172Same product: Microsoft Windows 10 1809
CVE-2023-36696Same product: Microsoft Windows 10 1809
CVE-2024-29994Same product: Microsoft Windows 10 1809
CVE-2023-24924Same product: Microsoft Windows 10 1809
CVE-2023-24872Same product: Microsoft Windows 10 1809
CVE-2023-21729Same product: Microsoft Windows 10 1809
CVE-2023-21769Same product: Microsoft Windows 10 1809

Affected Assets

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 server 2019
all versions
microsoft
windows server 2022
all versions

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.

ID.RA-01 partial match
blocks

Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.

PR.PS-02 partial match
blocks

Routine patching replaces vulnerable code containing out-of-bounds read flaws.

PR.PS-06 partial match
blocks

Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.

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.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References