• Sublime Core Feed

Description

Impersonation of the Microsoft brand.

@amitchell516
Created Aug 17th, 2023 • Last updated Oct 9th, 2025
Source
type.inbound
and (
  length(body.links) < 30
  or sender.email.local_part == "newsletter" and length(body.links) < 5
)
and (
  (
    strings.ilike(subject.subject, '*Microsoft 365*')
    and strings.ilike(subject.subject, '*is expired*')
  )
  or (
    // should catch any instance of the word "expired"
    strings.ilike(body.current_thread.text, "*expir*")
    and strings.ilike(body.current_thread.text, "*password*")
    and strings.ilike(body.current_thread.text, "*microsoft*")
  )
  or regex.icontains(body.current_thread.text,
                     ".*reach you.{0,20}Microsoft Teams"
  )
  or strings.ilike(sender.display_name, '*new activity in Teams*')
  or strings.icontains(strings.replace_confusables(sender.display_name),
                       'microsoft advertising support'
  )
  or subject.subject =~ 'Offline Message in Teams'
  or strings.ilike(subject.subject, '*Teams Sent A Message')
  or sender.display_name in~ (
    'Microsoft Partner Network',
    'Microsoft Advertising',
    'Microsoft',
    'Microsoft Feedback',
    'Microsoft account team',
    'Microsoft Support',
    'Microsoft 365 Message center',
    'Microsoft Azure'
  )
  or regex.icontains(sender.display_name,
                     "[MḾṀṂⱮМḿṁṃᵯⱮ𝐌𝑀][iíìîïīĭĩįıɪɨᵢⁱ𝐢𝑖][cćĉċčçƈȼ𝐜𝑐][rŕŗřȑȓɾᵣⁿʳ𝐫𝑟][oóòôõöøōŏőɵₒᵒº𝐨𝑜][sśŝšșşʂᵴˢˢ𝐬𝑠][oóòôõöøōŏőɵₒᵒº𝐨𝑜][fḟƒᵮᶠ𝐟𝑓][tťțţᵵₜᵗᵗ𝐭𝑡]"
  )
  or regex.icontains(sender.display_name,
                     "[MḾṀṂⱮМḿṁṃᵯⱮ𝐌𝑀][iíìîïīĭĩįıɪɨᵢⁱ𝐢𝑖][rŕŗřȑȓɾᵣⁿʳ𝐫𝑟][cćĉċčçƈȼ𝐜𝑐][oóòôõöøōŏőɵₒᵒº𝐨𝑜][sśŝšșşʂᵴˢˢ𝐬𝑠][oóòôõöøōŏőɵₒᵒº𝐨𝑜][fḟƒᵮᶠ𝐟𝑓][tťțţᵵₜᵗᵗ𝐭𝑡]" // [sic]
  )
)
and sender.email.domain.root_domain not in~ (
  'microsoft.com',
  'microsoftstoreemail.com',
  'microsoftsupport.com',
  'office.com',
  'teams-events.com',
  'qualtrics-research.com',
  'skype.com',
  'azureadnotifications.us',
  'microsoftonline.us',
  'mail.microsoft',
  'office365.com',
  'microsoftadvertising.com'
)
and not (
  sender.email.domain.domain in~ (
    'microsoft.regsvc.com',
    'microsoft.onmicrosoft.com'
  )
  and headers.auth_summary.dmarc.pass
)
and (
  profile.by_sender().prevalence in ("new", "outlier")
  or (
    profile.by_sender().any_messages_malicious_or_spam
    and not profile.by_sender().any_messages_benign
  )
)

// negate legitimate Office 365 bouncebacks
and not (
  all(attachments,
      .content_type in ("message/delivery-status", "message/rfc822")
  )
  and (
    sender.email.local_part in ('postmaster', 'mailer-daemon')
    or strings.starts_with(sender.email.local_part, 'microsoftexchange')
  )
  and (
    strings.contains(subject.subject, 'Undeliverable:')
    or strings.contains(subject.subject, 'Blocked:')
    or strings.contains(subject.subject, 'Não é possível entregar:')
  )
)

// negate other legitimate MS notifications
and not (
  length(body.links) > 0
  and all(body.links,
          .href_url.domain.root_domain in (
            "aka.ms",
            "microsoftonline.com",
            "microsoft.com"
          )
          or .href_url.domain.tld == "microsoft"
  )
  and headers.auth_summary.dmarc.pass
)

// negate highly trusted sender domains unless they fail DMARC authentication
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
)
// not a newsletter or advertisement
and not any(beta.ml_topic(body.current_thread.text).topics,
            .name in ("Newsletters and Digests")
            and .confidence == "high"
            and (
              any(body.links,
                  strings.icontains(.display_text, "unsubscribe")
                  and (strings.icontains(.href_url.path, "unsubscribe"))
              )
            )
)
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