alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET EXPLOIT Possible dlink-DSL2640B DNS Change Attempt"; flow:to_server,established; http.method; content:"GET"; http.uri; content:"/ddnsmngr.cmd?action=apply"; fast_pattern; content:"dnsPrimary="; content:"&dnsSecondary="; content:"&dnsDynamic="; content:"&dnsRefresh="; reference:url,packetstormsecurity.com/files/130418/dlink-DSL2640B.txt; classtype:attempted-user; sid:2020485; rev:4; metadata:created_at 2015_02_19, confidence Medium, signature_severity Major, updated_at 2020_09_29;)