alert tcp $EXTERNAL_NET any -> $HOME_NET [23,2323,3323,4323] (msg:"ET HUNTING SUSPICIOUS Path to BusyBox"; flow:established,to_server; content:"/bin/busybox"; flowbits:set,ET.telnet.busybox; threshold:type limit, count 1, track by_src, seconds 30; reference:url,lists.emergingthreats.net/pipermail/emerging-sigs/2016-August/027524.html; classtype:suspicious-filename-detect; sid:2023016; rev:2; metadata:attack_target Server, created_at 2016_08_08, deployment Datacenter, performance_impact Low, confidence Medium, signature_severity Major, updated_at 2022_04_18;)