Yes. There is an option for that. But it is not tested on such a huge range.
It appears to be working. These are the ranges I put in. We are a local blog, most of the SPAM is coming from these IPs overseas.
77.0.0.0-95.255.255.255
109.0.0.0-126.255.255.255
175.0.0.0-183.255.255.255
185.0.0.0-191.255.255.255
193.0.0.0-197.255.255.255
210.0.0.0-215.255.255.255
218.0.0.0-223.255.255.255
I have tried banning using wildcards:
195.154.*.*
62.210.*.*
94.23.*.*
188.165.*.*
37.59.*.*
– but my website statistics show that thousands of pages are still being accessed from these IPs:
IP Pages Last Visit
— —– ———-
192.99.14.166 2,268 28 Jan 2015 – 23:26
195.154.232.169 1,665 22 Jan 2015 – 14:25
62.210.142.7 1,082 28 Jan 2015 – 23:44
94.23.12.169 1,042 28 Jan 2015 – 16:37
188.165.213.170 1,012 28 Jan 2015 – 23:58
94.23.1.20 1,008 25 Jan 2015 – 23:39
62.210.122.209 899 28 Jan 2015 – 23:11
188.165.233.138 836 28 Jan 2015 – 23:45