Detection rules › Sigma

Suspicious Regsvr32 Execution From Remote Share

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

Detects REGSVR32.exe to execute DLL hosted on remote shares

MITRE ATT&CK coverage

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

title: Suspicious Regsvr32 Execution From Remote Share
id: 88a87a10-384b-4ad7-8871-2f9bf9259ce5
status: test
description: Detects REGSVR32.exe to execute DLL hosted on remote shares
references:
    - https://thedfirreport.com/2022/10/31/follina-exploit-leads-to-domain-compromise/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-10-31
tags:
    - attack.stealth
    - attack.t1218.010
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\regsvr32.exe'
        - OriginalFileName: '\REGSVR32.EXE'
    selection_cli:
        CommandLine|contains: ' \\\\'
    condition: all of selection_*
falsepositives:
    - Unknown
# Decrease to medium if this is something common in your org
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith: '\regsvr32.exe'
    - OriginalFileName: '\REGSVR32.EXE'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains: ' \\\\'

Indicators

These rows show field, operator, and value matches.