CVE-2026-21250
Published: 10 February 2026
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 29.7% of CVEs by exploit likelihood; 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
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Flaw remediation directly addresses the CVE by requiring timely patching of the untrusted pointer dereference in the HTTP.sys kernel driver.
Memory protection implements safeguards like DEP and ASLR that prevent exploitation of untrusted pointer dereferences for privilege escalation.
Least functionality minimizes exposure by disabling or restricting unnecessary kernel drivers like HTTP.sys when not essential for operations.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Local kernel-mode pointer dereference in HTTP.sys directly enables exploitation for privilege escalation from low-privileged local context.
NVD Description
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.
Deeper analysisAI
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.
Details
- CWE(s)