Detection rules › Sigma

LOLBAS Data Exfiltration by DataSvcUtil.exe

Status
test
Severity
medium
Log source
product windows, category process_creation
Author
Ialle Teixeira @teixeira0xfffff, Austin Songer @austinsonger
Source
github.com/SigmaHQ/sigma

Detects when a user performs data exfiltration by using DataSvcUtil.exe

MITRE ATT&CK coverage

TacticTechniques
ExfiltrationT1567 Exfiltration Over Web Service

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

title: LOLBAS Data Exfiltration by DataSvcUtil.exe
id: e290b10b-1023-4452-a4a9-eb31a9013b3a
status: test
description: Detects when a user performs data exfiltration by using DataSvcUtil.exe
references:
    - https://gist.github.com/teixeira0xfffff/837e5bfed0d1b0a29a7cb1e5dbdd9ca6
    - https://learn.microsoft.com/en-us/previous-versions/dotnet/framework/data/wcf/wcf-data-service-client-utility-datasvcutil-exe
    - https://learn.microsoft.com/en-us/previous-versions/dotnet/framework/data/wcf/generating-the-data-service-client-library-wcf-data-services
    - https://learn.microsoft.com/en-us/previous-versions/dotnet/framework/data/wcf/how-to-add-a-data-service-reference-wcf-data-services
    - https://lolbas-project.github.io/lolbas/Binaries/DataSvcUtil/
author: Ialle Teixeira @teixeira0xfffff, Austin Songer @austinsonger
date: 2021-09-30
modified: 2022-05-16
tags:
    - attack.exfiltration
    - attack.t1567
logsource:
    category: process_creation
    product: windows
detection:
    selection_cli:
        CommandLine|contains:
            - '/in:'
            - '/out:'
            - '/uri:'
    selection_img:
        - Image|endswith: '\DataSvcUtil.exe'
        - OriginalFileName: 'DataSvcUtil.exe'
    condition: all of selection*
falsepositives:
    - DataSvcUtil.exe being used may be performed by a system administrator.
    - Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
    - DataSvcUtil.exe being executed from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium

Stages and Predicates

Stage 0: condition

all of selection*

Stage 1: selection_cli

selection_cli:
    CommandLine|contains:
        - '/in:'
        - '/out:'
        - '/uri:'

Stage 2: selection_img

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

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
CommandLinematch
  • /in:
  • /out:
  • /uri:
Imageends_with
  • \DataSvcUtil.exe
OriginalFileNameeq
  • DataSvcUtil.exe