sublimemediumRule

Open redirect: City of Calgary

Message contains use of calgary.ca's open redirect but the sender is not the City of Calgary.

MITRE ATT&CK

T1566 T1566.001 T1566.002 T1598 T1190 T1203

executioninitial-access

Detection Query

type.inbound
and any(body.links,
        .href_url.domain.root_domain == 'calgary.ca'
        and .href_url.path =~ '/_layouts/cocis/DirectDownload.aspx'
        and strings.icontains(.href_url.query_params, "redirect")
)
and sender.email.domain.root_domain != 'calgary.ca'

// 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
)

Data Sources

Email MessagesEmail HeadersEmail Attachments

Platforms

Raw Content

name: "Open redirect: City of Calgary"
description: "Message contains use of calgary.ca's open redirect but the sender is not the City of Calgary."
type: "rule"
severity: "medium"
source: |
  type.inbound
  and any(body.links,
          .href_url.domain.root_domain == 'calgary.ca'
          and .href_url.path =~ '/_layouts/cocis/DirectDownload.aspx'
          and strings.icontains(.href_url.query_params, "redirect")
  )
  and sender.email.domain.root_domain != 'calgary.ca'
  
  // 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"
tactics_and_techniques:
  - "Exploit"
  - "Open redirect"
  - "Social engineering"
detection_methods:
  - "Sender analysis"
  - "URL analysis"
id: "00321858-7e21-5886-969b-530a2f023582"