Cyber Posture

CVE-2026-27907

High

Published: 14 April 2026

Published
14 April 2026
Modified
23 April 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 0.0007 20.7th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-27907 is a high-severity Wrap or Wraparound (CWE-191) vulnerability in Microsoft Windows 11 23H2. 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 20.7th 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-16 (Memory Protection) and SI-2 (Flaw Remediation).

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 mitigates the integer underflow vulnerability by requiring timely application of Microsoft patches for the Windows Storage Spaces Controller flaw.

prevent

Implements memory protections such as ASLR and DEP that thwart exploitation of integer underflow leading to memory corruption and privilege escalation.

prevent

Enforces least privilege for local accounts, limiting the scope and impact of low-privileged attackers attempting to exploit the vulnerability for escalation.

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?

Integer underflow in Windows kernel-mode Storage Spaces component directly enables local privilege escalation from low-privileged context (T1068).

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

NVD Description

Integer underflow (wrap or wraparound) in Windows Storage Spaces Controller allows an authorized attacker to elevate privileges locally.

Deeper analysisAI

CVE-2026-27907, published on 2026-04-14, is an integer underflow vulnerability (CWE-191) in the Windows Storage Spaces Controller. This flaw enables an authorized attacker to elevate privileges locally and 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 impact on confidentiality, integrity, and availability.

A local attacker with low privileges (PR:L) can exploit the vulnerability with low attack complexity (AC:L) and no user interaction (UI:N). Successful exploitation allows privilege escalation, providing the attacker with unauthorized high-level access that compromises system confidentiality, integrity, and availability without changing scope.

For details on mitigations, patches, and remediation steps, security practitioners should consult the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27907.

Details

CWE(s)

Affected Products

microsoft
windows 11 23h2
≤ 10.0.22631.6936 · ≤ 10.0.22631.6936
microsoft
windows 11 24h2
≤ 10.0.26100.8246 · ≤ 10.0.26100.8246
microsoft
windows 11 25h2
≤ 10.0.26200.8246 · ≤ 10.0.26200.8246
microsoft
windows 11 26h1
≤ 10.0.28000.1836 · ≤ 10.0.28000.1836
microsoft
windows server 2022 23h2
≤ 10.0.25398.2274
microsoft
windows server 2025
≤ 10.0.26100.32690

CVEs Like This One

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CVE-2026-21232Same product: Microsoft Windows 11 23H2
CVE-2026-33101Same product: Microsoft Windows 11 24H2
CVE-2026-20811Same product: Microsoft Windows 11 23H2
CVE-2026-24293Same product: Microsoft Windows 11 23H2
CVE-2026-25167Same product: Microsoft Windows 11 24H2
CVE-2026-32222Same product: Microsoft Windows 11 24H2

References