What is this?

[dageir]

A person sent me a chat and starts writing commands in the chat field. Is this some attempt of exploit, or is it just trolling?

[Devourer_of_Pancakes]

It's probably an honest attempt to use console commands in chat. Such functionality is pretty common in online games.

[dageir]

Is it normal to do this in chat?

[ameba]

Is it normal to do this in chat?

That depends on your definition of 'normal'.
However, while it may have been an attempt of exploiting anything, it will fail, as (from what I've learned) game commands are not executed through chat, but rather through console that opens up when typing ":" sign with focus out of chat box. And even then you're quite limited at what you can control with that, unless you have that dev client v.1.1.

[Devourer_of_Pancakes]

Is it normal to do this in chat?

I've played a fair number of games where you can use console commands in regular chat, so yeah, it's sort of normal.

Actual console commands shouldn't let players cheat; at least no more than the client allows. So using them (or trying to) is pretty harmless (if annoying when it's done in private messages).

Technically it's possible to try to hack a game server using chat (or even other players' game clients). But that would look completely different. If the same guy/gal sends you messages like "; DROP TABLE USERS;", you better report him/her

[martinuzz]

I still remember clearly how in H&H, at a certain point a few people found a way to crash nearby player's clients, by typing something in chat.

[Ass_Kraken]

I still remember clearly how in H&H, at a certain point a few people found a way to crash nearby player's clients, by typing something in chat.

By sending really long messages, not anything specific.