diff --git a/src/lib/ndpi_bitmap64.c b/src/lib/ndpi_bitmap64.c
index f2d5bec892d1..64635291e4d9 100644
--- a/src/lib/ndpi_bitmap64.c
+++ b/src/lib/ndpi_bitmap64.c
@@ -174,6 +174,8 @@ bool ndpi_bitmap64_isset(ndpi_bitmap64 *_b, u_int64_t value) {
     return(false);
 
   if(!b->is_compressed) ndpi_bitmap64_compress(b);
+  if(!b->is_compressed) /* Compresssion might fail */
+    return(false);
 
   return(binary_fuse16_contain(value, &b->bitmap));
 }
@@ -201,6 +203,8 @@ u_int32_t ndpi_bitmap64_size(ndpi_bitmap64 *_b) {
 
   if(!b) return(0);
   if(!b->is_compressed) ndpi_bitmap64_compress(b);
+  if(!b->is_compressed) /* Compresssion might fail */
+    return(0);
   
   return(sizeof(ndpi_bitmap64) + binary_fuse16_size_in_bytes(&b->bitmap));
 }