Bot/Hacker in the forum?

[DensetsuNoKaboom]

I have noticed that occasionally a post will contain, along with its original message, the following link:

nha khoa

It's not always the same user whose messages get these. The link appears to be to a Vietnamese dental clinic's website, which as you can probably tell has nothing to do with Alice at all.

It is my opinion that this may be caused by a bot or a hacker.

I am concerned, partly because I have no way of knowing that the site is not malicious (and I won't risk my computer by looking), but mostly because if this is the work of a hacker, it's a matter of time before someone follows the same lead, but not as harmless...

The first post in this topic is an example of an affected message.
As you can see in the second post in this thread, a similar link appeared in the first post, but was removed.