diff --git a/BinaryObjectScanner/FileType/CFB.cs b/BinaryObjectScanner/FileType/CFB.cs
index c8c115b8..d2e24503 100644
--- a/BinaryObjectScanner/FileType/CFB.cs
+++ b/BinaryObjectScanner/FileType/CFB.cs
@@ -556,7 +556,7 @@ namespace BinaryObjectScanner.FileType
 
                 // Handle version 3 entries
                 if (majorVersion == 3)
-                    directoryEntry.StreamSize &= 0x0000FFFF;
+                    directoryEntry.StreamSize &= 0x00000000FFFFFFFF;
 
                 directoryEntries[i] = directoryEntry;
             }