alert http $EXTERNAL_NET $HTTP_PORTS -> $HOME_NET any (msg:"ET EXPLOIT libPNG - Width exceeds limit"; flow:established,from_server; file_data; content:"|89 50 4E 47 0D 0A 1A 0A|"; depth:8; byte_test:4,>,0x80000000,8,relative,big,string,hex; reference:url,www.securiteam.com/unixfocus/5ZP0C0KDPG.html; classtype:misc-activity; sid:2001191; rev:13; metadata:created_at 2010_07_30, confidence Medium, signature_severity Major, updated_at 2019_07_26;)