Open redirect: k-mil.net

name: "Open redirect: k-mil.net"
description: |
  Message contains use of the k-mil.net open redirect. This has been exploited in the wild.
type: "rule"
severity: "medium"
source: |
  type.inbound
  and any(body.links,
          .href_url.domain.root_domain == "k-mil.net"
          and strings.iends_with(.href_url.path, 'official_url')
          and strings.icontains(.href_url.query_params, 'u=')
          and not regex.icontains(.href_url.query_params,
                                  'u=(?:https?(?:%3a|:))?(?:%2f|\/){2}[^&]*k-mil\.net(?:\&|\/|$)'
          )
  )
  and not sender.email.domain.root_domain == "k-mil.net"
  // 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
  )
attack_types:
  - "Credential Phishing"
  - "Malware/Ransomware"
tactics_and_techniques:
  - "Open redirect"
detection_methods:
  - "Sender analysis"
  - "URL analysis"
id: "9f422356-1ee1-5135-9132-a45cf14c802e"