CVE-2026-20846
Published: 10 February 2026
Summary
CVE-2026-20846 is a high-severity Buffer Over-read (CWE-126) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 19.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
Threat & Defense at a Glance
Threat & Defense Details
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Buffer over-read in GDI+ directly enables remote application exploitation resulting in endpoint DoS (high availability impact).
NVD Description
Buffer over-read in Windows GDI+ allows an unauthorized attacker to deny service over a network.
Deeper analysisAI
CVE-2026-20846 is a buffer over-read vulnerability (CWE-126) in the Windows GDI+ graphics component. Published on 2026-02-10, it carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), indicating high severity primarily due to its potential for availability disruption.
An unauthorized attacker can exploit this vulnerability remotely over a network with low attack complexity, requiring no user privileges or interaction. Successful exploitation results in a denial-of-service condition with high impact on availability, but no impact on confidentiality or integrity.
The Microsoft Security Response Center has published an update guide detailing mitigations for CVE-2026-20846 at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20846.
Details
- CWE(s)