• Sublime Core Feed
Medium Severity

Credential phishing: Tax form impersonation with payment request

Description

Detects messages impersonating tax-related communications that contain payment requests and PDF links, excluding legitimate tax service providers. The rule identifies tax terminology combined with payment solicitation language and PDF link references, which is a common pattern in tax season scams.

References

No references.

Sublime Security
Created Sep 10th, 2025 • Last updated Sep 10th, 2025
Source
type.inbound
and any([body.current_thread.text, subject.subject],
        regex.icontains(.,
                        'schedule.c\b',
                        'tax.form',
                        '1099\b',
                        '\bw-?2\b',
                        'tax.return',
                        'tax.preparation'
        )
        and (
          regex.icontains(body.current_thread.text,
                          "reply.with.your.payment",
                          "payment.details",
                          "send.payment.information",
                          "provide.payment",
                          "payment.method",
                          "billing.information",
                          "processing.fee",
                          "completion.fee"
          )
        )
        and any(body.links, strings.icontains(.display_text, "PDF"))
)
and not any(ml.nlu_classifier(body.current_thread.text).topics,
            .name in ("Events and Webinars", "Newsletters and Digests")
)
and not sender.email.domain.root_domain in (
  "intuit.com",
  "hrblock.com",
  "turbotax.com",
  "taxact.com",
  "freetaxusa.com",
  "geico.com",
  "email1.geico.com",
  "exs.eventshq.com",
  "square.com"
)
// 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
)
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