Brand impersonation: KnowBe4

 1name: "Brand impersonation: KnowBe4"
 2description: "Impersonation of KnowBe4."
 3type: "rule"
 4severity: "medium"
 5source: |
 6  type.inbound
 7  and (
 8    sender.display_name =~ 'KnowBe4'
 9    or strings.ilevenshtein(sender.display_name, 'KnowBe4') <= 1
10    or strings.icontains(sender.email.domain.domain, '*KnowBe4*')
11  )
12  and (
13    sender.email.domain.root_domain not in ('knowbe4.com')
14    or (
15      sender.email.domain.root_domain in ('knowbe4.com')
16      and not headers.auth_summary.dmarc.pass
17    )
18  )
19  
20  // negate highly trusted sender domains unless they fail DMARC authentication
21  and (
22    (
23      sender.email.domain.root_domain in $high_trust_sender_root_domains
24      and not headers.auth_summary.dmarc.pass
25    )
26    or sender.email.domain.root_domain not in $high_trust_sender_root_domains
27  )  
28attack_types:
29  - "Credential Phishing"
30  - "Spam"
31tactics_and_techniques:
32  - "Free email provider"
33  - "Impersonation: Brand"
34  - "Lookalike domain"
35  - "Social engineering"
36detection_methods:
37  - "Computer Vision"
38  - "Header analysis"
39  - "Sender analysis"
40id: "7c798386-fd25-5890-83b3-85187adbfc44"