Detection rules › Sublime MQL
Service abuse: Google Drive share from an unsolicited reply-to address
Identifies messages appearing to come from Google Drive sharing notifications that contain a reply-to address not previously seen in organizational communications. This tactic exploits trust in legitimate Google services while attempting to establish unauthorized communication channels.
Threat classification
Sublime's own taxonomy (not MITRE ATT&CK).
| Category | Values |
|---|---|
| Attack types | BEC/Fraud, Callback Phishing, Credential Phishing |
| Tactics and techniques | Free email provider, Social engineering, Free file host |
Event coverage
| Message attribute |
|---|
| headers (collection) |
| headers.reply_to (collection) |
| sender.email |
| type |
Rule body MQL
type.inbound
and sender.email.email in (
'drive-shares-dm-noreply@google.com',
'drive-shares-noreply@google.com',
)
and not any(headers.reply_to, .email.domain.domain in $org_domains)
//
// This rule makes use of a beta feature and is subject to change without notice
// using the beta feature in custom rules is not suggested until it has been formally released
//
// reply-to address has never sent an email to the org
and beta.profile.by_reply_to().prevalence == "new"
// reply-to email address has never been sent an email by the org
and not beta.profile.by_reply_to().solicited
// do not match if the reply_to address has been observed as a reply_to address
// of a message that has been classified as benign
and not beta.profile.by_reply_to().any_messages_benign
Detection logic
Scope: inbound message.
Identifies messages appearing to come from Google Drive sharing notifications that contain a reply-to address not previously seen in organizational communications. This tactic exploits trust in legitimate Google services while attempting to establish unauthorized communication channels.
- inbound message
- sender.email.email in ('drive-shares-dm-noreply@google.com', 'drive-shares-noreply@google.com')
not:
any of
headers.reply_towhere:- .email.domain.domain in $org_domains
- beta.profile.by_reply_to().prevalence is 'new'
not:
- beta.profile.by_reply_to().solicited
not:
- beta.profile.by_reply_to().any_messages_benign
Inspects: headers.reply_to, headers.reply_to[].email.domain.domain, sender.email.email, type.inbound. Sensors: beta.profile.by_reply_to. Reference lists: $org_domains.
Indicators matched (2)
| Field | Match | Value |
|---|---|---|
sender.email.email | member | drive-shares-dm-noreply@google.com |
sender.email.email | member | drive-shares-noreply@google.com |