The latter part of the URL query is a base64 string that resolves to somthing encoded:
4cf7bc5626b00a7a592836cb9cc9c34a|1|DirectLink|TXlPYmZ1Y2F0ZSBCb2R5TGF5ZXI=|1000|59016823
Virustotal does report the site as a "Malware Site".
https://www.virustotal.com/en/url/a9cb3cf6e43d2aa16485674a43128473493c66d1c3fad41534f373aeaf251c8f/analysis/
You should look into your web server logs to figure out how/when this code got injected in the first place. Is it because your sever is compromised or is it because you are using some vulnerable plugin ? is it because of malvertisement ?
A proper look at the codes and a complete clean-up would be required to avoid any future infections.