Yap, 403 with wget as well.
I used this ;
curl --header 'Host:
www.ossec.net' --header 'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:31.0) Gecko/20100101 Firefox/31.0' --header 'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8' --header 'Accept-Language: en-US,en;q=0.5' --header 'DNT: 1' --header 'Referer:
http://www.ossec.net/?page_id=19' --header 'Connection: keep-alive' '
http://www.ossec.net/files/ossec-hids-2.8.tar.gz' -o 'ossec-hids-2.8.tar.gz' -L
curl --header 'Host:
www.ossec.net' --header 'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:31.0) Gecko/20100101 Firefox/31.0' --header 'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8' --header 'Accept-Language: en-US,en;q=0.5' --header 'DNT: 1' --header 'Content-Type: application/x-www-form-urlencoded' '
http://www.ossec.net/files/ossec-hids-2.8-checksum.txt' -O -J -L