• Sublime Core Feed
Medium Severity

Mass campaign: Cross Site Scripting (XSS) attempt

Labels

Malware/Ransomware
Spam
Exploit
Free email provider
Scripting
Social engineering
Content analysis
Header analysis
Sender analysis

Description

Message subject or body contains Cross Site Scripting (XSS) indicators, and was sent to multiple unknown senders. Known spam technique.

References

No references.

Sublime Security
Created Mar 27th, 2024 • Last updated Jul 16th, 2025
Feed Source
Sublime Core Feed
Source
GitHub
type.inbound
and (
  length(recipients.to) > 10
  and length(filter(recipients.to,
                    .email.domain.domain not in $org_domains
                    and .email.email not in $recipient_emails
                    and (
                      .email.domain.valid
                      or strings.icontains(.display_name, "undisclosed")
                    )
             )
  ) >= 10
)
and (
  strings.ilike(subject.subject,
                '*<*script*>*',
                '*xss.report*',
                '*eval(atob*',
                '*<*onload*>*',
                '*<*onerror*>*'
  )
  or strings.ilike(body.current_thread.text,
                   '*<*script*>*',
                   '*xss.report*',
                   '*eval(atob*',
                   '*<*onload*>*',
                   '*<*onerror*>*'
  )
)
and (
  length(body.links) == 0
  or (
    length(body.links) == 1
    and all(body.links, .href_url.domain.domain == "this.id")
  )
)
and profile.by_sender().prevalence != "common"
and not profile.by_sender().solicited
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 (
      any(distinct(headers.hops, .authentication_results.dmarc is not null),
          strings.ilike(.authentication_results.dmarc, "*fail")
      )
    )
  )
  or sender.email.domain.root_domain not in $high_trust_sender_root_domains
)
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