Open redirect: buildingengines.com

 1name: "Open redirect: buildingengines.com"
 2description: |
 3  Detects messages containing buildingengines.com redirect links that use the _redirectTo
 4  parameter to redirect users to malicious sites. This has been observed in phishing campaigns.  
 5type: "rule"
 6severity: "medium"
 7source: |
 8  type.inbound
 9  and any(body.links,
10          // Look for buildingengines URLs
11          .href_url.domain.domain == "app.buildingengines.com"
12          and strings.icontains(.href_url.query_params, '_redirectTo=')
13          // Make sure it's not redirecting back to buildingengines.com
14          and not regex.icontains(.href_url.query_params,
15                                  '_redirectTo=(?:https?(?:%3a|:))?(?:%2f|\/){2}[^&]*buildingengines\.com(?:\&|\/|$|%2f)'
16          )
17  )
18  // Exclude legitimate Building Engines domains as senders
19  and not sender.email.domain.root_domain == "buildingengines.com"
20  
21  // negate highly trusted sender domains unless they fail DMARC authentication
22  and not (
23    sender.email.domain.root_domain in $high_trust_sender_root_domains
24    and coalesce(headers.auth_summary.dmarc.pass, false)
25  )  
26attack_types:
27  - "Credential Phishing"
28  - "Malware/Ransomware"
29tactics_and_techniques:
30  - "Open redirect"
31detection_methods:
32  - "Sender analysis"
33  - "URL analysis"
34id: "93df711e-8aea-5bd9-952f-a80d616b0cf0"