Enable LM Hash Storage - ProcCreation

Status: test
Severity: high
Log source: category process_creation, product windows
Author: Nasreddine Bencherchali (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects changes to the "NoLMHash" registry value in order to allow Windows to store LM Hashes. By setting this registry value to "0" (DWORD), Windows will be allowed to store a LAN manager hash of your password in Active Directory and local SAM databases.

MITRE ATT&CK coverage

Tactic	Techniques
Persistence	`T1112` Modify Registry
Defense Impairment	`T1112` Modify Registry

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation
Security-Auditing	Event ID 4688: A new process has been created.

Rule body

title: Enable LM Hash Storage - ProcCreation
id: 98dedfdd-8333-49d4-9f23-d7018cccae53
related:
    - id: c420410f-c2d8-4010-856b-dffe21866437 # Registry
      type: similar
status: test
description: |
    Detects changes to the "NoLMHash" registry value in order to allow Windows to store LM Hashes.
    By setting this registry value to "0" (DWORD), Windows will be allowed to store a LAN manager hash of your password in Active Directory and local SAM databases.
references:
    - https://www.cisa.gov/news-events/cybersecurity-advisories/aa23-347a
    - https://learn.microsoft.com/en-us/troubleshoot/windows-server/windows-security/prevent-windows-store-lm-hash-password
    - https://www.sans.org/blog/protecting-privileged-domain-accounts-lm-hashes-the-good-the-bad-and-the-ugly/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-12-15
modified: 2023-12-22
tags:
    - attack.persistence
    - attack.defense-impairment
    - attack.t1112
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        CommandLine|contains|all:
            - '\System\CurrentControlSet\Control\Lsa'
            - 'NoLMHash'
            - ' 0'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    CommandLine|contains|all:
        - '\System\CurrentControlSet\Control\Lsa'
        - 'NoLMHash'
        - ' 0'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`0` corpus 3 (sigma 3) `NoLMHash` `\System\CurrentControlSet\Control\Lsa` corpus 4 (sigma 4)	`field:"CommandLine" kind:match`