Command Injection in Windows Notepad - CVE-2026-20841
Published: February 10, 2026 / Updated: February 13, 2026
Vulnerability identifier: #VU122564
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber
CVE-ID: CVE-2026-20841
CWE-ID: CWE-77
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vendor: Microsoft
Affected software:
Windows Notepad
Windows Notepad
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary commands on the system.
The vulnerability exists due to insufficient input validation in Windows Notepad App. A remote attacker can trick a victim into clicking a malicious link inside a Markdown file opened in Notepad and execute arbitrary commands.
How to mitigate CVE-2026-20841
Install updates from vendor's website.