Cyber Posture

CVE-2026-21232

High

Published: 10 February 2026

Published
10 February 2026
Modified
11 February 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 0.0004 11.6th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-21232 is a high-severity Untrusted Pointer Dereference (CWE-822) 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 11.6th 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 remediates the untrusted pointer dereference vulnerability in Windows HTTP.sys by requiring timely installation of Microsoft patches.

prevent

Employs memory protection mechanisms such as ASLR and DEP to mitigate exploitation of the pointer dereference in the kernel-mode HTTP.sys driver.

prevent

Enforces least privilege on local low-privilege accounts, limiting the scope and impact of privilege escalation attempts via this 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 untrusted pointer dereference in kernel driver directly enables exploitation for privilege escalation to SYSTEM-level access.

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

NVD Description

Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.

Deeper analysisAI

CVE-2026-21232 is an untrusted pointer dereference vulnerability, classified under CWE-822, affecting the Windows HTTP.sys kernel-mode driver. This component handles HTTP requests in Windows operating systems. Published on 2026-02-10, the vulnerability 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.

A local attacker with low privileges (PR:L) can exploit this vulnerability through low-complexity actions requiring no user interaction. Exploitation enables privilege escalation, granting the attacker high-level impacts on confidentiality, integrity, and availability, potentially allowing full system compromise from an initial low-privilege position.

Microsoft's advisory provides mitigation guidance, available at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21232. Security practitioners should consult this update guide for patching instructions and recommended actions.

Details

CWE(s)

Affected Products

microsoft
windows 11 23h2
≤ 10.0.22631.6649 · ≤ 10.0.22631.6649
microsoft
windows 11 24h2
≤ 10.0.26100.7781 · ≤ 10.0.26100.7781
microsoft
windows 11 25h2
≤ 10.0.26200.7781 · ≤ 10.0.26200.7781
microsoft
windows server 2022 23h2
≤ 10.0.25398.2149
microsoft
windows server 2025
≤ 10.0.26100.32313

CVEs Like This One

CVE-2026-21250Same product: Microsoft Windows 11 24H2
CVE-2026-20938Same product: Microsoft Windows 11 23H2
CVE-2026-20811Same product: Microsoft Windows 11 23H2
CVE-2025-24084Same product: Microsoft Windows 11 23H2
CVE-2026-32222Same product: Microsoft Windows 11 24H2
CVE-2026-20857Same product: Microsoft Windows 11 23H2
CVE-2026-32077Same product: Microsoft Windows 11 23H2
CVE-2026-27919Same product: Microsoft Windows 11 23H2
CVE-2026-27920Same product: Microsoft Windows 11 23H2
CVE-2026-27907Same product: Microsoft Windows 11 23H2

References