Open redirect: City of Calgary

 1name: "Open redirect: City of Calgary"
 2description: "Message contains use of calgary.ca's open redirect but the sender is not the City of Calgary."
 3type: "rule"
 4severity: "medium"
 5source: |
 6  type.inbound
 7  and any(body.links,
 8          .href_url.domain.root_domain == 'calgary.ca'
 9          and .href_url.path =~ '/_layouts/cocis/DirectDownload.aspx'
10          and strings.icontains(.href_url.query_params, "redirect")
11  )
12  and sender.email.domain.root_domain != 'calgary.ca'
13  and (
14    not profile.by_sender().solicited
15    or (
16      profile.by_sender().any_messages_malicious_or_spam
17      and not profile.by_sender().any_false_positives
18    )
19  )
20  
21  // negate highly trusted sender domains unless they fail DMARC authentication
22  and (
23    (
24      sender.email.domain.root_domain in $high_trust_sender_root_domains
25      and not headers.auth_summary.dmarc.pass
26    )
27    or sender.email.domain.root_domain not in $high_trust_sender_root_domains
28  )  
29attack_types:
30  - "Credential Phishing"
31tactics_and_techniques:
32  - "Exploit"
33  - "Open redirect"
34  - "Social engineering"
35detection_methods:
36  - "Sender analysis"
37  - "URL analysis"
38id: "00321858-7e21-5886-969b-530a2f023582"