diff --git a/reactos/subsys/system/cmd/copy.c b/reactos/subsys/system/cmd/copy.c
index 4613e856647..60af3368f05 100644
--- a/reactos/subsys/system/cmd/copy.c
+++ b/reactos/subsys/system/cmd/copy.c
@@ -274,7 +274,7 @@ INT cmd_copy (LPTSTR cmd, LPTSTR param)
   nErrorLevel = 0;
 
   /* Get the envor value if it exists */
-  evar = malloc(512);
+  evar = malloc(512 * sizeof(TCHAR));
   if (evar==NULL) size = 0;
 
   size = GetEnvironmentVariable (_T("COPYCMD"), evar, 512);