Bitlocker Key Retrieval

Status: test
Severity: medium
Log source: product azure, service auditlogs
Author: Michael Epping, '@mepples21'
Source: github.com/SigmaHQ/sigma

Monitor and alert for Bitlocker key retrieval.

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1078.004` Valid Accounts: Cloud Accounts
Persistence	`T1078.004` Valid Accounts: Cloud Accounts
Privilege Escalation	`T1078.004` Valid Accounts: Cloud Accounts
Stealth	`T1078.004` Valid Accounts: Cloud Accounts

Telemetry coverage

Platform	Record / event type
Azure	Read BitLocker key

Rule body

title: Bitlocker Key Retrieval
id: a0413867-daf3-43dd-9245-734b3a787942
status: test
description: Monitor and alert for Bitlocker key retrieval.
references:
    - https://learn.microsoft.com/en-us/entra/architecture/security-operations-devices#bitlocker-key-retrieval
author: Michael Epping, '@mepples21'
date: 2022-06-28
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.initial-access
    - attack.stealth
    - attack.t1078.004
logsource:
    product: azure
    service: auditlogs
detection:
    selection:
        Category: KeyManagement
        OperationName: Read BitLocker key
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    Category: KeyManagement
    OperationName: Read BitLocker key

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`Category`	eq	`KeyManagement`	`field:"Category" kind:eq value:"KeyManagement"`
`OperationName`	eq	`Read BitLocker key`	`field:"OperationName" kind:eq value:"Read BitLocker key"`

Bitlocker Key Retrieval

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`