• Sublime Core Feed

Description

Body contains language resembling credential theft, and an attached "secure message" from an untrusted sender.

References

No references.

Sublime Security
Created May 2nd, 2024 • Last updated Jan 12th, 2026
Source
type.inbound
and any(ml.nlu_classifier(body.current_thread.text).intents,
        .name == "cred_theft" and .confidence == "high"
)

// ----- other suspicious signals here -----
and any(attachments,
        any(file.explode(.),
            any(.scan.strings.strings, strings.icontains(., "secure message"))
            and (
              any(.scan.url.urls, .domain.tld in $suspicious_tlds)
              or any(.scan.url.urls,
                     any(.rewrite.encoders,
                         strings.icontains(., "open_redirect")
                     )
              )
            )
            and (
              any(.scan.url.urls,
                  .domain.root_domain != sender.email.domain.root_domain
              )
              or not sender.email.domain.valid
            )
        )
)

// negate legitimate message senders
and (
  (
    sender.email.domain.root_domain not in ("protectedtrust.com")
    or not sender.email.domain.valid
  )
  and any(headers.hops,
          .index == 0
          and not any(.fields,
                      strings.contains(.value,
                                       'multipart/mixed; boundary="PROOFPOINT_BOUNDARY_1"'
                      )
          )
  )
  and not (
    any(headers.hops, any(.fields, .name == 'X-ZixNet'))
    and any(headers.domains,
            .root_domain in ("zixport.com", "zixcorp.com", "zixmail.net")
    )
  )
  and not all(body.links,
              .href_url.domain.root_domain in ("mimecast.com", "cisco.com")
  )
)
and (
  (
    profile.by_sender().prevalence in ("new", "outlier")
    and not profile.by_sender().solicited
  )
  or (
    profile.by_sender().any_messages_malicious_or_spam
    and not profile.by_sender().any_messages_benign
  )
)
and not profile.by_sender().any_messages_benign

// 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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