alert tcp $EXTERNAL_NET any -> $HOME_NET 139 (msg:"GPL NETBIOS NT NULL session"; flow:to_server,established; content:"|00 00 00 00|W|00|i|00|n|00|d|00|o|00|w|00|s|00| |00|N|00|T|00| |00|1|00|3|00|8|00|1"; reference:arachnids,204; reference:bugtraq,1163; reference:cve,2000-0347; classtype:attempted-recon; sid:2100530; rev:11; metadata:created_at 2010_09_23, cve CVE_2000_0347, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)