alert dns any any -> any any (msg:"🐾 - 🚨 Malicious 👿 BlankGrabber random DNS Request"; flow:to_server, stateless; dns_query; content:"blank-"; startswith; pcre:"/^blank-[a-z0-9]{5}.in$/"; content:".in"; endswith; reference:url,https://malpedia.caad.fkie.fraunhofer.de/details/py.blankgrabber; reference:url,https://c-b.io/blog/dissecting_blankgrabber/; metadata:attack_target Client_and_Server, signature_severity Major, affected_product Windows_XP_Vista_7_8_10_11_Server_32_64_Bit, mitre_tactic_id TA0011, mitre_tactic_name Command_and_Control, mitre_technique_id T1071.001, mitre_technique_name Application_Layer_Protocol_Web_Protocols, former_category MALWARE, malware_family BlankGrabber, created_at 2025_03_16, updated_at 2025_03_16; sid:3321424; rev:1; classtype:trojan-activity;)