Brand impersonation: USPS

  1name: "Brand impersonation: USPS"
  2description: "Impersonation of the United States Postal Service."
  3type: "rule"
  4severity: "high"
  5source: |
  6  type.inbound
  7  and (
  8    any(ml.logo_detect(file.message_screenshot()).brands, .name == "USPS")
  9    or strings.icontains(sender.display_name, "USPS")
 10    or regex.contains(body.html.display_text, 'USPS\s*\.\s*COM')
 11  )
 12  and length(body.links) > 0
 13  and 3 of (
 14    any(body.links,
 15        strings.ilike(.display_text,
 16                      "*check now*",
 17                      "*track*",
 18                      "*package*",
 19                      '*view your order*'
 20        )
 21    ),
 22    strings.ilike(body.current_thread.text,
 23                  "*returned*to*sender*",
 24                  "*redelivery*",
 25                  '*USPS promotions*',
 26                  '*review your package*',
 27                  '*receiver address*',
 28                  '*sorry tolet*',
 29                  '*Due to an incorrect*'
 30    ),
 31    // impersonal greeting
 32    any(ml.nlu_classifier(body.current_thread.text).entities,
 33        .name == "recipient" and .text =~ "Customer"
 34    ),
 35    // free email sender
 36    sender.email.domain.root_domain in $free_email_providers,
 37    // contains link to recently registered domain
 38    any(body.links, network.whois(.href_url.domain).days_old < 15),
 39    (
 40      regex.icontains(strings.replace_confusables(body.html.display_text),
 41                      '\b(?:u.?s.?p.?s|shipping|delivery)\b'
 42      )
 43      and not regex.icontains(body.html.display_text,
 44                              '\b(?:usps|shipping|delivery)\b'
 45      )
 46    )
 47  )
 48  and (
 49    sender.email.domain.root_domain not in (
 50      "usps.com",
 51      "opinions-inmoment.com", // https://faq.usps.com/s/article/USPS-Customer-Experience-Surveys
 52      "shipup.co", // third party shipping company
 53      "withings.com" // third party shipping company
 54    )
 55    or (
 56      sender.email.domain.root_domain in (
 57        "usps.com",
 58        "opinions-inmoment.com" // https://faq.usps.com/s/article/USPS-Customer-Experience-Surveys
 59      )
 60      and not headers.auth_summary.dmarc.pass
 61    )
 62  )
 63  // negate newsletters
 64  and not (
 65    length(body.links) > 20
 66    or any(ml.nlu_classifier(body.html.display_text).topics,
 67           .name == "Newsletters and Digests"
 68    )
 69  )
 70  // not all links to usps.com
 71  and not all(body.links, .href_url.domain.root_domain == "usps.com")
 72  // negate legit forwards and replies
 73  and not (
 74    (subject.is_reply or subject.is_forward)
 75    and length(body.previous_threads) > 0
 76    and (length(headers.references) > 0 or headers.in_reply_to is not null)
 77  )
 78  // negate highly trusted sender domains unless they fail DMARC authentication
 79  and (
 80    (
 81      sender.email.domain.root_domain in $high_trust_sender_root_domains
 82      and not headers.auth_summary.dmarc.pass
 83    )
 84    or sender.email.domain.root_domain not in $high_trust_sender_root_domains
 85  )
 86  and not any(body.links,
 87              regex.icontains(.display_text, 'Track (?:Your Order|Shipment)')
 88              and .href_url.domain.domain == 'tools.usps.com'
 89  )
 90  and not sender.email.domain.root_domain in ('shopifyemail.com')  
 91attack_types:
 92  - "Credential Phishing"
 93tactics_and_techniques:
 94  - "Image as content"
 95  - "Impersonation: Brand"
 96  - "Social engineering"
 97detection_methods:
 98  - "Computer Vision"
 99  - "Content analysis"
100  - "Natural Language Understanding"
101  - "Sender analysis"
102id: "28b9130a-d8e0-50af-97c9-c1b8f4c46d68"