diff --git a/src/hotspot/os/windows/os_windows.cpp b/src/hotspot/os/windows/os_windows.cpp
index 7cab20c7df0..1d2954014a3 100644
--- a/src/hotspot/os/windows/os_windows.cpp
+++ b/src/hotspot/os/windows/os_windows.cpp
@@ -1888,6 +1888,10 @@ void os::get_summary_cpu_info(char* buf, size_t buflen) {
     status = RegQueryValueEx(key, "ProcessorNameString", NULL, NULL, (byte*)buf, &size);
     if (status != ERROR_SUCCESS) {
         strncpy(buf, "## __CPU__", buflen);
+    } else {
+      if (size < buflen) {
+        buf[size] = '\0';
+      }
     }
     RegCloseKey(key);
   } else {