WORLDEDIT-2381 - Reported by odium

With use-inventory enabled (config.yml) users are able to duplicate items by performing the following action:

A) Select a container block with both hpos1 and hpos2
B) Use a set or replace command (/set stone) - The containerblock will then change and the items contained will spill from it.
C) Type /undo - The chest will return, with items that had already spilled out in tact; Thus duplicating the items.

Note: In some instances this will also cause the minecraft client of anyone within the region to crash, however the /undo history is retained and the spilled items remain so duplication still occurs.

The exploit is introduced sometime after WorldEdit-5.3

Comment by jb_aero

You don't want them duplicating items but you give them WorldEdit?

Comment by wizjany

This is an intrinsic flaw with use inventory if you give users anything beyond basic manipulation and generation.

Comment by odium

Users of a certain rank/group are given only basic WE functions, in this case only /set with a limit of 50 blocks and 'use-inventory' enabled.
As of recent builds, that alone is enough to cause the issue, which has not existed before.

It is an exploit, which requires fixing.
The use-inventory / allow-override functionality in WorldEdit can no longer be used while this exploit exists.

Comment by odium

Fair enough, I've fixed the exploit myself.

#225