Cyber Resilience

CVE-2026-21250

Microsoft Windows 11 24H2 ≤ 10.0.26100.7781

Published
10 February 2026
Modified
11 February 2026
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.010 61th percentile
Risk Priority 59 floored blend · peak EPSS

Summary

CVE-2026-21250 is a high-severity Untrusted Pointer Dereference (CWE-822) vulnerability in Microsoft Windows 11 24H2. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 39% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

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-2026-21250 is an untrusted pointer dereference vulnerability (CWE-822) in the Windows HTTP.sys kernel-mode driver. Published on 2026-02-10, 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) and affects Windows systems that rely on HTTP.sys for handling HTTP requests and responses.

The vulnerability can be exploited by an authorized local attacker with low privileges. Exploitation requires low complexity and no user interaction, allowing the attacker to elevate privileges and gain high-impact control over confidentiality, integrity, and availability of the affected system.

Microsoft's security update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21250 details available patches and mitigation recommendations for addressing this issue.

EU & UK References

Vulnerability Data

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

CWE(s)
CWE-822

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 →
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-2026-21232Same product: Microsoft Windows 11 24H2
CVE-2025-55677Same product: Microsoft Windows 11 24H2
CVE-2026-40369Same product: Microsoft Windows 11 24H2
CVE-2026-32222Same product: Microsoft Windows 11 24H2
CVE-2026-50424Same product: Microsoft Windows 11 24H2
CVE-2025-29812Same product: Microsoft Windows 11 24H2
CVE-2025-24084Same product: Microsoft Windows 11 24H2
CVE-2026-20811Same product: Microsoft Windows 11 24H2
CVE-2026-20938Same product: Microsoft Windows 11 24H2
CVE-2026-20857Same product: Microsoft Windows 11 24H2

Affected Assets

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

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover instances where untrusted data is turned into a pointer and dereferenced.

SI-10 Information Input Validation good match

Validating all information inputs stops untrusted values from being accepted and converted into dereferenceable pointers.

SI-16 Memory Protection partial match

Memory-protection mechanisms limit the damage from an invalid pointer dereference without stopping the root coding flaw.

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 SDLC practices directly prevent introduction of untrusted pointer handling during development.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data can detect adverse events resulting from exploitation of the weakness.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover instances of this weakness via code review or scanning.

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 can detect pointer-dereference flaws before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle includes pointer-safety practices that reduce untrusted pointer dereference risk.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate validation of pointers obtained from untrusted sources.

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

Secure architecture principles discourage direct use of untrusted values as pointers.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid dereferencing pointers derived from untrusted input.

References