Cyber Resilience

CVE-2023-21819

Memory Safety in Microsoft Windows 10 1809 ≤ 10.0.17763.4010

Memory Safety
Published
14 February 2023
Modified
21 November 2024
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

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 Exploitation for Privilege Escalation (T1068); 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

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
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-2023-35357Same product: Microsoft Windows 10 1809
CVE-2023-36696Same product: Microsoft Windows 10 1809
CVE-2024-26172Same product: Microsoft Windows 10 1809
CVE-2023-35358Same product: Microsoft Windows 10 1809
CVE-2024-29994Same product: Microsoft Windows 10 1809
CVE-2023-21729Same product: Microsoft Windows 10 1809
CVE-2023-24872Same product: Microsoft Windows 10 1809
CVE-2023-24924Same 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.

PR.PS-06 mostly match
prevents

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

ID.RA-01 partial match
prevents

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

PR.PS-02 partial match
prevents

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

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.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance includes fuzzing and static analysis that detect out-of-bounds read defects before release.

A.8.15 Logging partial match
finds

Logging can record evidence of an out-of-bounds read but does not prevent the weakness itself.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and bounds checking that directly prevent out-of-bounds reads.

A.8.26 Application security requirements partial match
prevents

Application security requirements include explicit bounds and memory-safety specifications that mitigate buffer over-reads.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure system architecture and engineering principles require memory-safe design patterns and runtime protections against out-of-bounds access.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid unsafe pointer arithmetic and mandate bounds-checked reads, eliminating CWE-125.

References