Detection rules › Splunk
Zoom Rare Audio Devices
Detects rare audio devices from Zoom logs. Actors performing Remote Employment Fraud (REF) typically use unusual device information compared to a majority of employees. Detecting this activity requires careful analysis, regular review, and a thorough understanding of the audio and video devices commonly used within your environment.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Collection | T1123 Audio Capture |
Rule body splunk
name: Zoom Rare Audio Devices
id: 9fdbf709-4c46-4819-9fb6-98b2d72059ed
version: 3
creation_date: '2025-06-12'
modification_date: '2026-05-13'
author: Marissa Bower, Raven Tait
status: experimental
type: Hunting
description: Detects rare audio devices from Zoom logs. Actors performing Remote Employment Fraud (REF) typically use unusual device information compared to a majority of employees. Detecting this activity requires careful analysis, regular review, and a thorough understanding of the audio and video devices commonly used within your environment.
data_source: []
search: |-
`zoom_index` speaker=* NOT (camera=*iPhone* OR camera="*FaceTime*" OR speaker="*AirPods*" OR camera="*MacBook*" OR microphone="*MacBook Pro Microphone*")
| rare speaker limit=50
| `zoom_rare_audio_devices_filter`
how_to_implement: The analytic leverages Zoom logs to be ingested using Splunk Connect for Zoom (https://splunkbase.splunk.com/app/4961)
known_false_positives: This is a hunting query meant to identify rare audio devices.
analytic_story:
- Remote Employment Fraud
asset_type: Identity
mitre_attack_id:
- T1123
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: application
security_domain: identity
Stages and Predicates
Stage 1: search
`zoom_index` speaker=* NOT (camera=*iPhone* OR camera="*FaceTime*" OR speaker="*AirPods*" OR camera="*MacBook*" OR microphone="*MacBook Pro Microphone*")
Stage 2: rare
| rare speaker limit=50
Stage 3: search
| `zoom_rare_audio_devices_filter`
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
camera | eq | *iPhone* |
camera | eq | "*FaceTime*" |
camera | eq | "*MacBook*" |
microphone | eq | "*MacBook Pro Microphone*" |
speaker | eq | "*AirPods*" |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
speaker | eq |
|