Detection rules › Sigma

NTLMv1 Logon Between Client and Server

Status
test
Severity
medium
Log source
product windows, service system
Author
Tim Shelton, Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the reporting of NTLMv1 being used between a client and server. NTLMv1 is insecure as the underlying encryption algorithms can be brute-forced by modern hardware.

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: NTLMv1 Logon Between Client and Server
id: e9d4ab66-a532-4ef7-a502-66a9e4a34f5d
status: test
description: Detects the reporting of NTLMv1 being used between a client and server. NTLMv1 is insecure as the underlying encryption algorithms can be brute-forced by modern hardware.
references:
    - https://github.com/nasbench/EVTX-ETW-Resources/blob/f1b010ce0ee1b71e3024180de1a3e67f99701fe4/ETWProvidersManifests/Windows10/22H2/W10_22H2_Pro_20230321_19045.2728/WEPExplorer/LsaSrv.xml
author: Tim Shelton, Nasreddine Bencherchali (Nextron Systems)
date: 2022-04-26
modified: 2023-06-06
tags:
    - attack.lateral-movement
    - attack.t1550.002
logsource:
    product: windows
    service: system
detection:
    selection:
        Provider_Name: "LsaSrv"
        EventID:
            - 6038
            - 6039
    condition: selection
falsepositives:
    - Environments that use NTLMv1
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Provider_Name: "LsaSrv"
    EventID:
        - 6038
        - 6039

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
Provider_Nameeq
  • LsaSrv