Considering this definition, I would say an equivalent might be “Dommage !” with irony in the tone of voice. But it seems to be very different from what you explained. Could you please develop your idea or give a few more examples ?

By the exemples found on urban dictinnary I think you can use something like :

bien fait pour toi / lui

If you want to mock the person.

If it is just an other way to say "that sucks" I think you can use swears like :

fait chier

merde

Well litteraly speaking that would be something like

C’est con d’être con !

That’s juste a game of words after all.

But in general, when people talk, they rather use

• C’est ballot !
• Quel dommage !
• Tel est pris qui croyait prendre !

And much more I don’t have right now

Dans ce contexte on peux dire :

Tant mieux pour lui !

Ça veut dire qu’il a mérité ce qui lui arrive.

In addition to the other (valid) answers, in such a situation, you could also hear some French speakers quote a famous sarcastic song by Georges Brassens:

Quand on est con, on est con.

It can be used if you want to comment a blatant example of a stupid person that won’t learn from their mistakes but that you don’t feel sorry for them.