Boot Configuration Tampering Via Bcdedit.EXE

Status: stable
Severity: high
Log source: category process_creation, product windows
Author: E.M. Anhaus (originally from Atomic Blue Detections, Endgame), oscd.community
Source: github.com/SigmaHQ/sigma

Detects the use of the bcdedit command to tamper with the boot configuration data. This technique is often times used by malware or attackers as a destructive way before launching ransomware.

Known false positives

Unlikely

MITRE ATT&CK coverage

Tactic	Techniques
Impact	`T1490` Inhibit System Recovery

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation

Rule body

title: Boot Configuration Tampering Via Bcdedit.EXE
id: 1444443e-6757-43e4-9ea4-c8fc705f79a2
status: stable
description: Detects the use of the bcdedit command to tamper with the boot configuration data. This technique is often times used by malware or attackers as a destructive way before launching ransomware.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1490/T1490.md
    - https://eqllib.readthedocs.io/en/latest/analytics/c4732632-9c1d-4980-9fa8-1d98c93f918e.html
author: E.M. Anhaus (originally from Atomic Blue Detections, Endgame), oscd.community
date: 2019-10-24
modified: 2023-02-15
tags:
    - attack.impact
    - attack.t1490
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\bcdedit.exe'
        - OriginalFileName: 'bcdedit.exe'
    selection_set:
        CommandLine|contains: 'set'
    selection_cli:
        - CommandLine|contains|all:
              - 'bootstatuspolicy'
              - 'ignoreallfailures'
        - CommandLine|contains|all:
              - 'recoveryenabled'
              - 'no'
    condition: all of selection_*
falsepositives:
    - Unlikely
level: high
simulation:
    - type: atomic-red-team
      name: Windows - Disable Windows Recovery Console Repair
      technique: T1490
      atomic_guid: cf21060a-80b3-4238-a595-22525de4ab81

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith: '\bcdedit.exe'
    - OriginalFileName: 'bcdedit.exe'

Stage 2: `selection_set`

selection_set:
    CommandLine|contains: 'set'

Stage 3: `selection_cli`

selection_cli:
    - CommandLine|contains|all:
          - 'bootstatuspolicy'
          - 'ignoreallfailures'
    - CommandLine|contains|all:
          - 'recoveryenabled'
          - 'no'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`bootstatuspolicy` corpus 10 (elastic 8, sigma 1, splunk 1) `ignoreallfailures` corpus 2 (sigma 1, splunk 1) `no` `recoveryenabled` corpus 10 (elastic 8, sigma 1, splunk 1) `set` corpus 11 (sigma 10, splunk 1)	`field:"CommandLine" kind:match`
`Image`	ends_with	`\bcdedit.exe` corpus 5 (sigma 5)	`field:"Image" kind:ends_with value:"\bcdedit.exe"`
`OriginalFileName`	eq	`bcdedit.exe` corpus 13 (elastic 11, sigma 2)	`field:"OriginalFileName" kind:eq value:"bcdedit.exe"`