diff --git a/UI/CwCheatScreen.cpp b/UI/CwCheatScreen.cpp
index 7f51ef3017..9e5863e536 100644
--- a/UI/CwCheatScreen.cpp
+++ b/UI/CwCheatScreen.cpp
@@ -154,19 +154,20 @@ UI::EventReturn CwCheatScreen::OnEditCheatFile(UI::EventParams &params) {
 	cheatFile = activeCheatFile;
 	// Can't rely on a .txt file extension to auto-open in the right editor,
 	// so let's find notepad
-	wchar_t notepad_path[MAX_PATH];
-	GetSystemDirectory(notepad_path, sizeof(notepad_path) / sizeof(wchar_t));
+	wchar_t notepad_path[MAX_PATH + 1];
+	GetSystemDirectory(notepad_path, MAX_PATH);
 	wcscat(notepad_path, L"\\notepad.exe");
 
-	wchar_t cheat_path[MAX_PATH];
-	wcscpy(cheat_path, ConvertUTF8ToWString(cheatFile).c_str());
+	wchar_t cheat_path[MAX_PATH + 1] = {0};
+	wcsncpy(cheat_path, ConvertUTF8ToWString(cheatFile).c_str(), MAX_PATH);
 	// Flip any slashes...
 	for (size_t i = 0; i < wcslen(cheat_path); i++) {
 		if (cheat_path[i] == '/')
 			cheat_path[i] = '\\';
 	}
 
-	wchar_t command_line[MAX_PATH * 2 + 1];
+	// One for the space, one for the null.
+	wchar_t command_line[MAX_PATH * 2 + 1 + 1];
 	wsprintf(command_line, L"%s %s", notepad_path, cheat_path);
 
 	STARTUPINFO si;