Rule History

alert tcp $EXTERNAL_NET any -> $HOME_NET [25,465,587] (msg:"ET EXPLOIT CVE-2015-0235 Exim Buffer Overflow Attempt (HELO)"; flow:to_server,established; content:"HELO "; nocase; content:!"|0a|"; within:1024; pcre:"/^\s*?\d[\d\x2e]{255}/R"; reference:url,openwall.com/lists/oss-security/2015/01/27/9; classtype:attempted-admin; sid:2020325; rev:3; metadata:created_at 2015_01_28, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_01_26;)