Detection rules › Sublime MQL

Service abuse: Calendly callback scam detection

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

Detects inbound messages from Calendly's notification system that contain callback scam content, as identified through natural language processing with medium or high confidence levels.

Threat classification

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

CategoryValues
Attack typesCallback Phishing
Tactics and techniquesSocial engineering, Impersonation: Brand

Event coverage

Rule body MQL

type.inbound
and sender.email.email == "no-reply@calendly.com"
and any(ml.nlu_classifier(body.current_thread.text).intents,
        .name == "callback_scam" and .confidence != "low"
)

Detection logic

Scope: inbound message.

Detects inbound messages from Calendly's notification system that contain callback scam content, as identified through natural language processing with medium or high confidence levels.

  1. inbound message
  2. sender.email.email is 'no-reply@calendly.com'
  3. any of ml.nlu_classifier(body.current_thread.text).intents where all hold:
    • .name is 'callback_scam'
    • .confidence is not 'low'

Inspects: body.current_thread.text, sender.email.email, type.inbound. Sensors: ml.nlu_classifier.

Indicators matched (2)

FieldMatchValue
sender.email.emailequalsno-reply@calendly.com
ml.nlu_classifier(body.current_thread.text).intents[].nameequalscallback_scam