Detectionmediumtest

NTLM Brute Force

Detects common NTLM brute force device names

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Launch
Jerry ShockleyCreated Wed Feb 029c8acf1a-cbf9-4db6-b63c-74baabe03e59windows
Log Source
Windowsntlm
ProductWindows← raw: windows
Servicentlm← raw: ntlm

Definition

Requires events from Microsoft-Windows-NTLM/Operational

Detection Logic
Detection Logic2 selectors
detection:
    selection:
        EventID: 8004
    devicename:
        WorkstationName:
            - 'Rdesktop'
            - 'Remmina'
            - 'Freerdp'
            - 'Windows7'
            - 'Windows8'
            - 'Windows2012'
            - 'Windows2016'
            - 'Windows2019'
    condition: selection and devicename
False Positives

Systems with names equal to the spoofed ones used by the brute force tools

Rule Metadata
Rule ID
9c8acf1a-cbf9-4db6-b63c-74baabe03e59
Status
test
Level
medium
Type
Detection
Created
Wed Feb 02
Path
rules/windows/builtin/ntlm/win_susp_ntlm_brute_force.yml
Raw Tags
attack.credential-accessattack.t1110
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