CVE-2026-20922
Published: 13 January 2026
Summary
CVE-2026-20922 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows Server 2008. 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 7.7th 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
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly remediates the heap-based buffer overflow vulnerability in Windows NTFS by identifying, reporting, and applying timely flaw corrections including patches from Microsoft.
Implements memory protection mechanisms to prevent exploitation of heap-based buffer overflows in the NTFS file system component.
Enforces least privilege to limit the scope and impact of arbitrary code execution achieved via local exploitation of the NTFS vulnerability.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Local heap buffer overflow in NTFS kernel component directly enables arbitrary code execution from low-privileged context, mapping to exploitation for privilege escalation.
NVD Description
Heap-based buffer overflow in Windows NTFS allows an authorized attacker to execute code locally.
Deeper analysisAI
CVE-2026-20922, published on 2026-01-13, is a heap-based buffer overflow vulnerability (CWE-122) in the Windows NTFS file system component. 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 with relatively low barriers to exploitation.
A local attacker with low privileges (PR:L) can exploit this vulnerability through local access (AV:L) with low attack complexity (AC:L) and no user interaction (UI:N). Successful exploitation enables arbitrary code execution in the context of the affected process, granting high impacts on confidentiality, integrity, and availability.
Microsoft's Security Response Center provides an update guide for mitigation details at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20922.
Details
- CWE(s)