• Sublime Core Feed
Medium Severity

Service abuse: Facebook business with action required subject

Description

Detects messages from the Facebook business domain containing 'action required' in the subject line, commonly used to create urgency in impersonation attacks.

References

No references.

Sublime Security
Created Nov 17th, 2025 • Last updated Nov 17th, 2025
Source
type.inbound
and (
  sender.email.domain.root_domain == "facebook.com"
  or sender.email.domain.root_domain == "facebookmail.com"
)
and 3 of (
  strings.icontains(subject.subject, "Action required"),
  strings.icontains(subject.subject, "invited to join"),
  strings.icontains(body.current_thread.text, "You've been invited"),
  strings.icontains(body.current_thread.text, "You're invited"),
  strings.icontains(body.current_thread.text,
                    "not part of or affiliated with Meta"
  )
)
and (
  // and the link is recently registered
  any(body.links, network.whois(.href_url.domain).days_old <= 30)
  or any(body.links,
         // if the link is still active, check if it's cred theft
         any(ml.nlu_classifier(beta.ocr(ml.link_analysis(.).screenshot).text).intents,
             .name == "cred_theft" and .confidence != "low"
         )
  )
  // or look for the legit Meta footer address
  or strings.icontains(body.current_thread.text,
                       '1 Meta Way, Menlo Park, CA 94025'
  )
)
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