diff --git a/detection-rules/attachment_html_recipient_in_javascript_identifiers.yml b/detection-rules/attachment_html_recipient_in_javascript_identifiers.yml index 849592d655b..92325b3de87 100644 --- a/detection-rules/attachment_html_recipient_in_javascript_identifiers.yml +++ b/detection-rules/attachment_html_recipient_in_javascript_identifiers.yml @@ -7,25 +7,29 @@ source: | type.inbound and any(attachments, ( - .file_extension in~ ("html", "htm", "shtml", "dhtml") + .file_extension in~ ("html", "htm", "shtml", "dhtml", "xhtml") or ( .file_extension is null and .file_type == "unknown" and .content_type == "application/octet-stream" - and .size < 100000000 ) or .file_extension in~ $file_extensions_common_archives or .file_type == "html" + or .content_type == "text/html" ) and any(file.explode(.), // suspicious identifiers - any(.scan.javascript.identifiers, strings.like(., "atob", "decrypt")) - // Recipients address found in javascript - and any(recipients.to, - any(..scan.javascript.strings, strings.icontains(., ..email.email)) + any([.scan.strings.strings, .scan.javascript.identifiers], + any(., strings.like(., "*atob*", "*decrypt*")) ) ) - ) + // Recipients address found in javascript + and any(file.explode(.), + any(recipients.to, + any(..scan.javascript.strings, strings.icontains(., ..email.email)) + ) + ) + ) attack_types: - "Credential Phishing" tactics_and_techniques: