alert dns $HOME_NET any -> any any (msg:"ET MALWARE ISMAgent DNS Lookup (msoffice-cdn . com)"; dns.query; content:"msoffice-cdn.com"; depth:16; nocase; endswith; fast_pattern; reference:md5,812d3c4fddf9bb81d507397345a29bb0; reference:url,www.clearskysec.com/ismagent/; classtype:trojan-activity; sid:2024620; rev:5; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_08_29, deployment Perimeter, performance_impact Moderate, confidence Medium, signature_severity Major, updated_at 2020_09_17;)