alert ftp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE W32.Qakbot Seclog FTP Upload"; flow:established,to_server; content:"seclog_"; content:".kcb"; within:30; pcre:"/seclog\x5F[a-z]{5}[0-9]{5}\x5F.+\x2Ekcb/smi"; reference:url,www.symantec.com/content/en/us/enterprise/media/security_response/whitepapers/w32_qakbot_in_detail.pdf; reference:url,www.symantec.com/security_response/writeup.jsp?docid=2009-050707-0639-99; classtype:trojan-activity; sid:2012975; rev:2; metadata:created_at 2011_06_09, signature_severity Major, updated_at 2019_07_26;)