Could you elaborate? I'm failing to see how is this a problem.
What data are you talking about? The only public data from user profiles are things like "Driven distance" or "Join date". How could this be abused? You don't have to share your personal info if you don't want to.
I would be amazed if since the beginning of this website there was no protection for this and noone abused it to this day. Even if that was true - you need to log in to an account to send a message so I'm pretty sure spam bot could be protected simply by restricting the amount of messages sent by a user in a specific time range or something like that. No need to redo the whole URL generating system for this (not to mention that's surely not the only thing that would have to be reworked).
createaxm.Info.Add(new ObjectInfo
{
X = short.Parse(StrMsg[3]) / 16,
Y = short.Parse(StrMsg[4]) / 16,
Zbyte = byte.Parse(StrMsg[5]),
});
createaxm.Info.Add(new ObjectInfo
{
X = short.Parse(StrMsg[3]),
Y = short.Parse(StrMsg[4]),
Zbyte = byte.Parse(StrMsg[5]),
});