Detection rules › Sublime MQL
Attachment with suspicious author (unsolicited)
Recursively scans files and archives to detect embedded docx files with a specific author.
Threat classification
Sublime's own taxonomy (not MITRE ATT&CK).
| Category | Values |
|---|---|
| Attack types | Malware/Ransomware |
Event coverage
| Message attribute |
|---|
| attachments (collection) |
| type |
Rule body MQL
type.inbound
and any(attachments,
(
.file_extension in~ ("doc", "docm", "docx", "dot", "dotm")
or .file_extension in~ $file_extensions_common_archives
)
and any(file.explode(.), strings.ilike(.scan.docx.author, "root"))
)
and (
not profile.by_sender().solicited
or (
profile.by_sender().any_messages_malicious_or_spam
and not profile.by_sender().any_messages_benign
)
)
Detection logic
Scope: inbound message.
Recursively scans files and archives to detect embedded docx files with a specific author.
- inbound message
any of
attachmentswhere all hold:any of:
- .file_extension in ('doc', 'docm', 'docx', 'dot', 'dotm')
- .file_extension in $file_extensions_common_archives
any of
file.explode(.)where:- .scan.docx.author matches 'root'
any of:
not:
- profile.by_sender().solicited
all of:
- profile.by_sender().any_messages_malicious_or_spam
not:
- profile.by_sender().any_messages_benign
Inspects: attachments[].file_extension, type.inbound. Sensors: file.explode, profile.by_sender, strings.ilike. Reference lists: $file_extensions_common_archives.
Indicators matched (6)
| Field | Match | Value |
|---|---|---|
attachments[].file_extension | member | doc |
attachments[].file_extension | member | docm |
attachments[].file_extension | member | docx |
attachments[].file_extension | member | dot |
attachments[].file_extension | member | dotm |
strings.ilike | substring | root |