Detection rules › Sublime MQL

Link: Intuit link abuse with file share context

Severity
medium
Type
rule
Source
github.com/sublime-security/sublime-rules

Detects messages linking to Intuit notification domains from non-Intuit senders, combined with credential harvesting language and file sharing themes

Threat classification

Sublime's own taxonomy (not MITRE ATT&CK).

CategoryValues
Attack typesCredential Phishing
Tactics and techniquesImpersonation: Brand, Social engineering

Event coverage

Rule body MQL

type.inbound
// look for links to links.notification.intuit.com but the sender is not from quickbooks/intuit
and any(body.links, .href_url.domain.domain == "links.notification.intuit.com")
and sender.email.domain.root_domain not in ("quickbooks.com", "intuit.com")
// check to see if it is classified as cred_theft
and any(ml.nlu_classifier(body.current_thread.text).intents,
        .name in ("cred_theft") and .confidence != "low"
)
and length(body.current_thread.text) < 1750
// check to see if the topic is File Sharing & Cloud Services
and any(beta.ml_topic(body.current_thread.text).topics,
        .name == "File Sharing and Cloud Services" and .confidence != "low"
)

Detection logic

Scope: inbound message.

Detects messages linking to Intuit notification domains from non-Intuit senders, combined with credential harvesting language and file sharing themes

  1. inbound message
  2. any of body.links where:
    • .href_url.domain.domain is 'links.notification.intuit.com'
  3. sender.email.domain.root_domain not in ('quickbooks.com', 'intuit.com')
  4. any of ml.nlu_classifier(body.current_thread.text).intents where all hold:
    • .name in ('cred_theft')
    • .confidence is not 'low'
  5. length(body.current_thread.text) < 1750
  6. any of beta.ml_topic(body.current_thread.text).topics where all hold:
    • .name is 'File Sharing and Cloud Services'
    • .confidence is not 'low'

Inspects: body.current_thread.text, body.links, body.links[].href_url.domain.domain, sender.email.domain.root_domain, type.inbound. Sensors: beta.ml_topic, ml.nlu_classifier.

Indicators matched (5)

FieldMatchValue
body.links[].href_url.domain.domainequalslinks.notification.intuit.com
sender.email.domain.root_domainmemberquickbooks.com
sender.email.domain.root_domainmemberintuit.com
ml.nlu_classifier(body.current_thread.text).intents[].namemembercred_theft
beta.ml_topic(body.current_thread.text).topics[].nameequalsFile Sharing and Cloud Services