Reported in Sourceforge - https://sourceforge.net/tracker/?funh1. detailaid2780481group_ih1. 205633atid1064496

Since switching to Xoops 2.3.3, SmartSection no longer correctly displays
the list of files attached to an article. The first entry is always garbled
and has an invalid id.

It looks like it's because in item.php, in the section 'Creating the files
object associated with this item' (line 123 and onwards), $file is not
initialized. It is set halfway down the loop, but used earlier than that.
Indeed, when I add:

unset ($file);

before the loop, it works perfectly. To me this was enough for a quick fix
on my own sites but I don't know the code well enough to know whether I
didn't break anything else. And anyway you might want to fix this in the
real release. :)

The strange thing is that this uninitialized use of $file has been in
SmartSection for a long time, but the problem only becomes apparant in
Xoops 2.3.x.