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That would be the safest thing to do. Depends on how much you know your server.
Looking at the logs (you should look at yours too) I can see they try to run commands, upload code to get a shell, just about anything.
Some things I see:
. "uname -a" to get the kernel version.
. "ls /tmp" "ls c:/" etc to browse around.
. "wget ...." to upload exploits and scripts.
So they might just browse around for kicks or delete everything you have. Whatever they want.
I think they depend on the rights of the web-server user. Secure your server. That was too close for comfort this time.