diff --git a/modules/contrib/src/inputoutput.cpp b/modules/contrib/src/inputoutput.cpp
index e04740fae..d6d514f5b 100644
--- a/modules/contrib/src/inputoutput.cpp
+++ b/modules/contrib/src/inputoutput.cpp
@@ -11,7 +11,7 @@
 
 namespace cv
 {
-    std::vector<std::string> Directory::GetListFiles(  const std::string& path, const std::string & exten, bool addPath )
+    std::vector<std::string> Directory::GetListFiles( const std::string& path, const std::string & exten, bool addPath )
     {
         std::vector<std::string> list;
         list.clear();
@@ -25,10 +25,9 @@ namespace cv
         HANDLE hFind;
 
         #ifdef HAVE_WINRT
-            size_t size = mbstowcs(NULL, path_f.c_str(), path_f.size());
-            Ptr<wchar_t> wpath = new wchar_t[size+1];
-            wpath[size] = 0;
-            mbstowcs(wpath, path_f.c_str(), path_f.size());
+            wchar_t wpath[MAX_PATH];
+            size_t copied = mbstowcs(wpath, path_f.c_str(), MAX_PATH);
+            CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
             hFind = FindFirstFileExW(wpath, FindExInfoStandard, &FindFileData, FindExSearchNameMatch, NULL, 0);
         #else
             hFind = FindFirstFileA((LPCSTR)path_f.c_str(), &FindFileData);
@@ -47,12 +46,12 @@ namespace cv
                         FindFileData.dwFileAttributes == FILE_ATTRIBUTE_SYSTEM  ||
                         FindFileData.dwFileAttributes == FILE_ATTRIBUTE_READONLY)
                     {
-                        cv::Ptr<char> fname;
+                        char* fname;
                     #ifdef HAVE_WINRT
-                        size_t asize = wcstombs(NULL, FindFileData.cFileName, 0);
-                        fname = new char[asize+1];
-                        fname[asize] = 0;
-                        wcstombs(fname, FindFileData.cFileName, asize);
+                        char fname_tmp[MAX_PATH] = {0};
+                        size_t copied = wcstombs(fname_tmp, FindFileData.cFileName, MAX_PATH);
+                        CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
+                        fname = fname_tmp;
                     #else
                         fname = FindFileData.cFileName;
                     #endif
@@ -109,10 +108,10 @@ namespace cv
             HANDLE hFind;
 
         #ifdef HAVE_WINRT
-            size_t size = mbstowcs(NULL, path_f.c_str(), path_f.size());
-            Ptr<wchar_t> wpath = new wchar_t[size+1];
-            wpath[size] = 0;
-            mbstowcs(wpath, path_f.c_str(), path_f.size());
+            wchar_t wpath [MAX_PATH];
+            size_t copied = mbstowcs(wpath, path_f.c_str(), path_f.size());
+            CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
+
             hFind = FindFirstFileExW(wpath, FindExInfoStandard, &FindFileData, FindExSearchNameMatch, NULL, 0);
         #else
             hFind = FindFirstFileA((LPCSTR)path_f.c_str(), &FindFileData);
@@ -135,12 +134,12 @@ namespace cv
                         strcmp(FindFileData.cFileName, "..") != 0)
 #endif
                     {
-                        cv::Ptr<char> fname;
+                        char* fname;
                     #ifdef HAVE_WINRT
-                        size_t asize = wcstombs(NULL, FindFileData.cFileName, 0);
-                        fname = new char[asize+1];
-                        fname[asize] = 0;
-                        wcstombs(fname, FindFileData.cFileName, asize);
+                        char fname_tmp[MAX_PATH];
+                        size_t copied = wcstombs(fname, FindFileData.cFileName, MAX_PATH);
+                        CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
+                        fname = fname_tmp;
                     #else
                         fname = FindFileData.cFileName;
                     #endif
diff --git a/modules/core/src/glob.cpp b/modules/core/src/glob.cpp
index e39cba016..208b4e05c 100644
--- a/modules/core/src/glob.cpp
+++ b/modules/core/src/glob.cpp
@@ -79,10 +79,9 @@ namespace
         dir->ent.d_name = 0;
 #ifdef HAVE_WINRT
         cv::String full_path = cv::String(path) + "\\*";
-        size_t size = mbstowcs(NULL, full_path.c_str(), full_path.size());
-        cv::Ptr<wchar_t> wfull_path = new wchar_t[size+1];
-        wfull_path[size] = 0;
-        mbstowcs(wfull_path, full_path.c_str(), full_path.size());
+        wchar_t wfull_path[MAX_PATH];
+        size_t copied = mbstowcs(wfull_path, full_path.c_str(), MAX_PATH);
+        CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
         dir->handle = ::FindFirstFileExW(wfull_path, FindExInfoStandard,
                         &dir->data, FindExSearchNameMatch, NULL, 0);
 #else
@@ -106,6 +105,7 @@ namespace
                 return 0;
         }
         size_t asize = wcstombs(NULL, dir->data.cFileName, 0);
+        CV_Assert((asize != 0) && (asize != (size_t)-1));
         char* aname = new char[asize+1];
         aname[asize] = 0;
         wcstombs(aname, dir->data.cFileName, asize);
@@ -146,10 +146,9 @@ static bool isDir(const cv::String& path, DIR* dir)
     {
         WIN32_FILE_ATTRIBUTE_DATA all_attrs;
 #ifdef HAVE_WINRT
-        size_t size = mbstowcs(NULL, path.c_str(), path.size());
-        cv::Ptr<wchar_t> wpath = new wchar_t[size+1];
-        wpath[size] = 0;
-        mbstowcs(wpath, path.c_str(), path.size());
+        wchar_t wpath[MAX_PATH];
+        size_t copied = mbstowcs(wpath, path.c_str(), MAX_PATH);
+        CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
         ::GetFileAttributesExW(wpath, GetFileExInfoStandard, &all_attrs);
 #else
         ::GetFileAttributesExA(path.c_str(), GetFileExInfoStandard, &all_attrs);
diff --git a/modules/core/src/system.cpp b/modules/core/src/system.cpp
index 7e01ca5ea..685b5b756 100644
--- a/modules/core/src/system.cpp
+++ b/modules/core/src/system.cpp
@@ -411,15 +411,14 @@ string tempfile( const char* suffix )
     temp_file = temp_dir + std::wstring(L"\\") + temp_file;
     DeleteFileW(temp_file.c_str());
 
-    size_t asize = wcstombs(NULL, temp_file.c_str(), 0);
-    Ptr<char> aname = new char[asize+1];
-    aname[asize] = 0;
-    wcstombs(aname, temp_file.c_str(), asize);
+    char aname[MAX_PATH];
+    size_t copied = wcstombs(aname, temp_file.c_str(), MAX_PATH);
+    CV_Assert((copied != MAX_PATH) && (copied != (size_t)-1));
     fname = std::string(aname);
     RoUninitialize();
 #else
-    char temp_dir2[MAX_PATH + 1] = { 0 };
-    char temp_file[MAX_PATH + 1] = { 0 };
+    char temp_dir2[MAX_PATH] = { 0 };
+    char temp_file[MAX_PATH] = { 0 };
 
     if (temp_dir == 0 || temp_dir[0] == 0)
     {