diff --git a/BaseTools/Source/C/Common/PcdValueCommon.c b/BaseTools/Source/C/Common/PcdValueCommon.c
index 32963e6c67..92328daa16 100644
--- a/BaseTools/Source/C/Common/PcdValueCommon.c
+++ b/BaseTools/Source/C/Common/PcdValueCommon.c
@@ -335,7 +335,7 @@ Returns:
       printf("%x\n", Byte);
       Value = End + 1;
     }
-    Buffer = malloc(*Size);
+    Buffer = malloc(*Size + 1);
     if (Buffer == NULL) {
       *Size = 0;
       return NULL;