alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Possible Covenant Framework Grunt PowerShell Stager HTTP Download"; flow:established,to_client; file.data; content:"IO.Compression.CompressionMode]|3a 3a|Decompress"; content:".Value.Write("; distance:0; content:"Reflection.Assembly]|3a 3a|Load("; fast_pattern; distance:0; content:".EntryPoint.Invoke("; distance:0; content:"Out-Null"; distance:0; reference:url,github.com/cobbr/Covenant; reference:url,posts.specterops.io/entering-a-covenant-net-command-and-control-e11038bcf462; classtype:trojan-activity; sid:2027797; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_08_04, deployment Perimeter, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_03_14;)