Notepad++

Notepad++ is a free and open-source source code editor. From 8.9.7 until 8.9.8, the Notepad++ updater and signature verification path can accept a modified GUP.exe file whose embedded certificate metadata remains present even though its Authenticode digest is invalid. An attacker who can replace or plant the updater-related file can cause Notepad++ to launch attacker-modified code when a user triggers the updater path, but the issue does not provide remote code execution by itself. This issue is fixed in version 8.9.8.

Notepad++ is a free and open-source source code editor. Prior to 8.9.8, the Folder as Workspace Run by system action in Notepad++ can resolve a different sibling file than the file selected by the user. When an attacker places a command script whose name is the selected text-file path with .cmd appended, and the user invokes Run by system on the text file on Windows 10 or Windows 11, Notepad++ can execute the sibling script as the current user instead of opening the selected file. This issue is fixed in version 8.9.8.

Notepad++ is a free and open-source source code editor. Prior to 8.9.8, Notepad++ contains a stack buffer overflow in NppParameters::writeSession in PowerEditor/src/Parameters.cpp because it copies a session path derived from -settingsDir= into backupPathName[MAX_PATH] with unbounded wcscpy and appends SESSION_BACKUP_EXT with unbounded wcscat. A sufficiently long settings directory causes the backup suffix to exceed the fixed stack buffer when Notepad++ saves the session, and the protected release build terminates through its stack canary, causing denial of service. This issue is fixed in version 8.9.8.

Notepad++ is a free and open-source source code editor. Prior to 8.9.8, Notepad++ contains a stack buffer overflow in PluginsManager::loadPluginFromPath in PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp because the plugin-supplied GetLexerCount() result controls a loop that writes to containers[30] without enforcing NB_MAX_EXTERNAL_LANG. A malicious or compromised plugin that reports more than 30 lexers can write beyond the stack array and corrupt control data, which can permit arbitrary code execution in the Notepad++ process context. This issue is fixed in version 8.9.8.

Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the WinGup decompress function joins untrusted ZIP entry names to unzipDestTo without canonical containment validation, allowing an entry such as ../mimeTools/mimeTools.dll to overwrite a DLL in a sibling plugin directory and execute attacker-controlled code when Notepad++ next loads that plugin. This issue is fixed in version 8.9.7.

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.