Cyber Posture

CVE-2026-23673

High

Published: 10 March 2026

Published
10 March 2026
Modified
13 March 2026
KEV Added
Patch
CVSS Score 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0003 8.7th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-23673 is a high-severity Out-of-bounds Read (CWE-125) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 8.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and AC-6 (Least Privilege).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Privilege Escalation (T1068). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly addresses the out-of-bounds read vulnerability in ReFS by requiring timely remediation through vendor patches as specified in the Microsoft advisory.

prevent

Implements memory protection mechanisms such as address space layout randomization and stack guards that mitigate exploitation of out-of-bounds reads in the file system.

prevent

Enforces least privilege to limit the impact of local low-privilege attackers attempting privilege escalation via the ReFS vulnerability.

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Local out-of-bounds read in ReFS directly enables privilege escalation from low-privileged context.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Out-of-bounds read in Windows Resilient File System (ReFS) allows an authorized attacker to elevate privileges locally.

Deeper analysisAI

CVE-2026-23673 is an out-of-bounds read vulnerability, classified under CWE-125, affecting the Windows Resilient File System (ReFS). Published on 2026-03-10, it carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for significant impact despite requiring local access.

A local attacker with low privileges (PR:L) can exploit this vulnerability with low complexity and no user interaction. Successful exploitation enables privilege escalation, granting high-level access that compromises confidentiality, integrity, and availability of the affected system.

Mitigation details are available in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23673.

Details

CWE(s)

Affected Products

microsoft
windows 10 1607
≤ 10.0.14393.8957 · ≤ 10.0.14393.8957
microsoft
windows 10 1809
≤ 10.0.17763.8511 · ≤ 10.0.17763.8511
microsoft
windows 10 21h2
≤ 10.0.19044.7058 · ≤ 10.0.19044.7058 · ≤ 10.0.19044.7058
microsoft
windows 10 22h2
≤ 10.0.19045.7058 · ≤ 10.0.19045.7058 · ≤ 10.0.19045.7058
microsoft
windows 11 23h2
≤ 10.0.22631.6783 · ≤ 10.0.22631.6783
microsoft
windows 11 24h2
≤ 10.0.26100.7979 · ≤ 10.0.26100.7979
microsoft
windows 11 25h2
≤ 10.0.26200.7979 · ≤ 10.0.26200.7979
microsoft
windows 11 26h1
≤ 10.0.28000.1719 · ≤ 10.0.28000.1719
microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
≤ 10.0.14393.8957
+4 more product configuration(s) — see NVD for full list

CVEs Like This One

CVE-2026-25174Same product: Microsoft Windows 10 1607
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CVE-2025-48822Same product: Microsoft Windows 10 1607
CVE-2026-25175Same product: Microsoft Windows 10 1607
CVE-2026-26156Same product: Microsoft Windows 10 1607
CVE-2026-27914Same product: Microsoft Windows 10 1607
CVE-2026-27915Same product: Microsoft Windows 10 1607
CVE-2026-25165Same product: Microsoft Windows 10 1607

References