diff --git a/src/metadata/makernotes.cpp b/src/metadata/makernotes.cpp
index 9433abd..7ae80f5 100644
--- a/src/metadata/makernotes.cpp
+++ b/src/metadata/makernotes.cpp
@@ -396,6 +396,7 @@ void LibRaw::parse_makernote(int base, int uptag)
     is_Sony = 1;
   }
 
+  memset(buf, '0', 10);
   fread(buf, 1, 10, ifp);
 
   if (!strncmp(buf, "KDK", 3)  || /* these aren't TIFF tables */