Description
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.
References3
Metrics
- CVSS 4.0
-
5.4
MEDIUM
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 9 · as of 12 November 2026
- CWE
- CWE-77
Could this be exploited in your environment?
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