diff --git a/detection-rules/impersonation_schwab.yml b/detection-rules/impersonation_schwab.yml new file mode 100644 index 00000000000..33b6a7ba916 --- /dev/null +++ b/detection-rules/impersonation_schwab.yml @@ -0,0 +1,66 @@ +name: "Brand impersonation: Charles Schwab" +description: "Impersonation of Charles Schwab & Co" +type: "rule" +severity: "medium" +source: | + type.inbound + and ( + // display name contains charles schwab + ( + strings.ilike(strings.replace_confusables(sender.display_name), + '*charles schwab*' + ) + // no spaces + or strings.ilike(strings.replace_confusables(sender.display_name), + '*charlesschwab*' + ) + // levenshtein distince similar to schwab + or strings.ilevenshtein(strings.replace_confusables(sender.display_name), + 'charles schwab' + ) <= 1 + // sender domain contains schwab + or strings.ilike(strings.replace_confusables(sender.email.domain.domain), + '*schwab*' + ) + ) + ) + + // and the sender is not in org_domains or from charles shwab domains and passes auth + and not ( + sender.email.domain.root_domain in $org_domains + or ( + ( + sender.email.domain.root_domain in ( + "schwab.com", + "aboutschwab.com.", + "schwabmoneywise.com", + "schwabe.com", // law firm with name + "proxyvote.com", // sends shareholder voting information with subject of company name + "boheme-schwabing.de", // steakhouse + "lesschwab.com", // tire sales + ) + or sender.email.domain.domain in ("schwabebooks.ccsend.com") + ) + and headers.auth_summary.dmarc.pass + ) + ) + // and the sender is not from high trust sender root domains + and ( + ( + sender.email.domain.root_domain in $high_trust_sender_root_domains + and not headers.auth_summary.dmarc.pass + ) + or sender.email.domain.root_domain not in $high_trust_sender_root_domains + ) + and not profile.by_sender().solicited + +attack_types: + - "Credential Phishing" +tactics_and_techniques: + - "Impersonation: Brand" + - "Lookalike domain" + - "Social engineering" +detection_methods: + - "Header analysis" + - "Sender analysis" +id: "7abde595-bd69-5b79-8031-2c5a12b1767e"