CVE-2026-73250

Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the Notepad++ Windows 11 x64 and ARM64 installer passes the attacker-influenced installation directory $INSTDIR from PowerEditor/installer/nppSetup.nsi into a PowerShell -Command string used by RegisterMSIX to invoke Add-AppxPackage, allowing PowerShell subexpression syntax such as $() in the installation path to execute commands in the installer's security context when the context menu component is selected. This issue is fixed in version 8.9.7.