diff -urNp old/plug-ins/common/file-gbr.c new/plug-ins/common/file-gbr.c
--- old/plug-ins/common/file-gbr.c	2018-01-04 12:13:17.553757864 +0100
+++ new/plug-ins/common/file-gbr.c	2018-01-04 12:18:01.723635742 +0100
@@ -443,7 +443,8 @@ load_image (const gchar  *filename,
     {
       gchar *temp = g_new (gchar, bn_size);
 
-      if ((read (fd, temp, bn_size)) < bn_size)
+      if ((read (fd, temp, bn_size)) < bn_size ||
+          temp[bn_size - 1] != '\0')
         {
           g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
                        _("Error in GIMP brush file '%s'"),