diff --git a/es-core/src/Log.cpp b/es-core/src/Log.cpp
index fe6585e81..e94480548 100644
--- a/es-core/src/Log.cpp
+++ b/es-core/src/Log.cpp
@@ -54,7 +54,15 @@ void Log::open()
 std::ostringstream& Log::get(LogLevel level)
 {
     time_t t = time(nullptr);
-    os << std::put_time(localtime(&t), "%b %d %T ") << logLevelMap[level] << ":\t";
+    struct tm tm;
+    #if defined(_WIN64)
+    // Of course Windows does not follow standards and puts the parameters the other way
+    // around compared to POSIX.
+    localtime_s(&tm, &t);
+    #else
+    localtime_r(&t, &tm);
+    #endif
+    os << std::put_time(&tm, "%b %d %T ") << logLevelMap[level] << ":\t";
     messageLevel = level;
 
     return os;
diff --git a/es-core/src/utils/TimeUtil.cpp b/es-core/src/utils/TimeUtil.cpp
index 10c79cf38..d4b5e87f9 100644
--- a/es-core/src/utils/TimeUtil.cpp
+++ b/es-core/src/utils/TimeUtil.cpp
@@ -44,7 +44,11 @@ namespace Utils
         void DateTime::setTime(const time_t& _time)
         {
             mTime = (_time < 0) ? 0 : _time;
-            mTimeStruct = *localtime(&mTime);
+            #if defined(_WIN64)
+            localtime_s(&mTimeStruct, &mTime);
+            #else
+            localtime_r(&mTime, &mTimeStruct);
+            #endif
             mIsoString = timeToString(mTime);
         }
 
@@ -171,7 +175,12 @@ namespace Utils
         std::string timeToString(const time_t& _time, const std::string& _format)
         {
             const char* f = _format.c_str();
-            const tm timeStruct = *localtime(&_time);
+            tm timeStruct;
+            #if defined(_WIN64)
+            localtime_s(&timeStruct, &_time);
+            #else
+            localtime_r(&_time, &timeStruct);
+            #endif
             char buf[256] = { '\0' };
             char* s = buf;