CVE-2026-54758
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the expandNppEnvironmentStrs function in PowerEditor/src/WinControls/StaticDialog/RunDlg/RunDlg.cpp copies a Notepad++ variable name between $( and ) into the fixed-size wchar_t str[MAX_PATH] stack buffer without bounding the m loop index, allowing a name of 260 or more characters to corrupt adjacent stack data, terminate the process through __report_gsfailure, and potentially execute code. This issue is fixed in version 8.9.7.
Risk Assessment
The vulnerability could lead to process crash or potential code execution, which could result in system compromise. However, the attack requires running a specially crafted command.
Recommendation
It is recommended to upgrade Notepad++ to version 8.9.7 or later. Also, avoid running untrusted commands with long environment variables.
Original NVD description (English source)
Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the expandNppEnvironmentStrs function in PowerEditor/src/WinControls/StaticDialog/RunDlg/RunDlg.cpp copies a Notepad++ variable name between $( and ) into the fixed-size wchar_t str[MAX_PATH] stack buffer without bounding the m loop index, allowing a name of 260 or more characters to corrupt adjacent stack data, terminate the process through __report_gsfailure, and potentially execute code. This issue is fixed in version 8.9.7.