Attachment: Office file contains OLE relationship to credential phishing page

 1name: "Attachment: Office file contains OLE relationship to credential phishing page"
 2description: |
 3    Office file OLE relationship link is a credential page, or contains credential phishing language.
 4type: "rule"
 5severity: "high"
 6source: |
 7  type.inbound
 8  and any(attachments,
 9          (
10            .file_extension in~ $file_extensions_macros
11            or (
12              .file_extension is null
13              and .file_type == "unknown"
14              and .content_type == "application/octet-stream"
15              and .size < 100000000
16            )
17          )
18          and length(file.oletools(.).relationships) < 500
19          and any(file.oletools(.).relationships,
20                  (
21                    any(ml.nlu_classifier(ml.link_analysis(.target_url).final_dom.display_text
22                        ).intents,
23                        .name == "cred_theft"
24                        and .confidence in ("medium", "high")
25                    )
26                    and .target_url.domain.root_domain not in ("google.com", "goo.gl")
27                   
28                    and ml.link_analysis(.target_url).effective_url.domain.domain != "login.microsoftonline.com"
29                  )
30                  or ml.link_analysis(.target_url).credphish.disposition == "phishing"
31          )
32  )
33  and (
34    (
35      profile.by_sender().prevalence in ("new", "outlier")
36      and not profile.by_sender().solicited
37    )
38    or (
39      profile.by_sender().any_messages_malicious_or_spam
40      and not profile.by_sender().any_false_positives
41    )
42  )  
43attack_types:
44  - "Credential Phishing"
45tactics_and_techniques:
46  - "Evasion"
47  - "Social engineering"
48detection_methods:
49  - "File analysis"
50  - "HTML analysis"
51  - "Natural Language Understanding"
52  - "OLE analysis"
53  - "URL analysis"
54id: "d55793d0-865e-53c4-ae51-f1b0fec50ec6"