Medium Severity

Service abuse: Fake loan/funding verification lure via Mailgun

Labels

Credential Phishing

Impersonation: Brand

Description

Detects inbound messages sent via Mailgun's sending infrastructure (mg subdomain) from common bulk sender addresses, where the body contains unresolved template placeholders like '[SOURCEID]', known Mailgun-associated physical addresses, or links pointing to Mailgun's campaign/list management subdomain (napp) on the same root domain as the sender. These indicators suggest automated bulk distribution with incomplete template rendering or suspicious infrastructure usage.

References

No references.

Sublime Security

Created Jun 29th, 2026 • Last updated Jun 29th, 2026

Feed Source

Sublime Core Feed

Source

GitHub

type.inbound
and sender.email.local_part in~ ("info", "no-reply", "noreply")
and sender.email.domain.subdomain == "mg"
and (
  any(body.links,
      .href_url.domain.subdomain == "napp"
      and .href_url.domain.root_domain == sender.email.domain.root_domain
      and (
        strings.istarts_with(.href_url.path, "/campaigns/")
        or strings.istarts_with(.href_url.path, "/lists/")
      )
  )
  or strings.icontains(body.current_thread.text,
                       "12603 State Route 143 Suite G",
                       "4049 US Highway 231 #2002 Wetumpka, AL 36093"
  )
  or strings.icontains(body.current_thread.text, "[SOURCEID]")
)

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