alert http1 $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE TA452 Related Backdoor Activity (POST)"; flow:established,to_server; http.method; content:"POST"; http.uri; bsize:4; content:"/put"; http.header_names; content:"|0d 0a|UserAgent|0d 0a|Host|0d 0a|Content-Length|0d 0a|Expect|0d 0a|"; startswith; fast_pattern; reference:md5,a3c14604fb4454ba5722f07f89780e73; reference:md5,c3aedb781a5b96674764cd43ef076d10; reference:url,twitter.com/StopMalvertisin/status/1562896289981136898; reference:url,www.safebreach.com/resources/blog/safebreach-labs-researchers-uncover-new-fully-undetectable-powershell-backdoor/; classtype:trojan-activity; sid:2039515; rev:3; metadata:attack_target Client_Endpoint, created_at 2022_10_24, deployment Perimeter, malware_family TA452, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_03;)