alert tcp $EXTERNAL_NET any -> $HOME_NET 445 (msg:"GPL NETBIOS SMB-DS Session Setup NTMLSSP andx asn1 overflow attempt"; flow:established,to_server; content:"|00|"; depth:1; content:"|FF|SMB"; within:4; distance:3; pcre:"/^(\x75|\x2d|\x2f|\xa2|\x2e|\x24|\x74)/sR"; byte_test:1,!&,128,6,relative; content:"s"; depth:1; offset:39; byte_jump:2,0,little,relative; byte_test:4,&,2147483648,21,relative,little; content:!"NTLMSSP"; within:7; distance:27; asn1:double_overflow, bitstring_overflow, relative_offset 27, oversize_length 2048; reference:bugtraq,9633; reference:bugtraq,9635; reference:cve,2003-0818; reference:nessus,12052; reference:nessus,12065; reference:url,www.microsoft.com/technet/security/bulletin/MS04-007.mspx; classtype:protocol-command-decode; sid:2103004; rev:5; metadata:created_at 2010_09_23, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)