Detection rules › Sigma

Guest User Invited By Non Approved Inviters

Status
test
Severity
medium
Log source
product azure, service auditlogs
Author
Mark Morowczynski '@markmorow', Yochana Henderson, '@Yochana-H'
Source
github.com/SigmaHQ/sigma

Detects when a user that doesn't have permissions to invite a guest user attempts to invite one.

MITRE ATT&CK coverage

Rule body yaml

title: Guest User Invited By Non Approved Inviters
id: 0b4b72e3-4c53-4d5b-b198-2c58cfef39a9
status: test
description: Detects when a user that doesn't have permissions to invite a guest user attempts to invite one.
references:
    - https://learn.microsoft.com/en-us/entra/architecture/security-operations-privileged-accounts#things-to-monitor
author: Mark Morowczynski '@markmorow', Yochana Henderson, '@Yochana-H'
date: 2022-08-10
tags:
    - attack.privilege-escalation
    - attack.initial-access
    - attack.persistence
    - attack.stealth
    - attack.t1078.004
logsource:
    product: azure
    service: auditlogs
detection:
    selection:
        properties.message: Invite external user
        Status: failure
    condition: selection
falsepositives:
    - A non malicious user is unaware of the proper process
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    properties.message: Invite external user
    Status: failure

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.

FieldKindValues
Statuseq
  • failure
properties.messageeq
  • Invite external user