New answers tagged hacking
The attacker is attempting to exploit the Bash Shellshock vulnerability. You can verify whether or not you're vulnerable with a couple simple command-line tests (which by themselves are not harmful), already covered in another SF post: How to test if my server is vulnerable to the ShellShock bug? Your logs show that they returned 200 HTTP status codes, ...
My preferred way of dealing with this is to block access to anything in the /wp-admin/ folder and /wp-login.php to everywhere except a known static IP, say the IP of your office. Barring that, look into fail2ban or any number of wordpress plugins that can handle mitigating these brute-force hacking attempts.
Yep, it probably is a series of attempts to compromise your server. Keep your entire system updated, don't use weak passwords, and keep a series of backups in case they manage to succeed.
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