Open redirect: City of Calgary

calendar Sep 23, 2026  ยท
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Message contains use of calgary.ca's open redirect but the sender is not the City of Calgary.

Sublime rule (View on GitHub)

 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  
14  // negate highly trusted sender domains unless they fail DMARC authentication
15  and not (
16    sender.email.domain.root_domain in $high_trust_sender_root_domains
17    and coalesce(headers.auth_summary.dmarc.pass, false)
18  )  
19attack_types:
20  - "Credential Phishing"
21tactics_and_techniques:
22  - "Exploit"
23  - "Open redirect"
24  - "Social engineering"
25detection_methods:
26  - "Sender analysis"
27  - "URL analysis"
28id: "00321858-7e21-5886-969b-530a2f023582"
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