Remote DLL Load Via Rundll32.EXE

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

Detects a remote DLL load event via "rundll32.exe".

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1204.002` User Execution: Malicious File

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 7: Image loaded

Rule body

title: Remote DLL Load Via Rundll32.EXE
id: f40017b3-cb2e-4335-ab5d-3babf679c1de
status: test
description: Detects a remote DLL load event via "rundll32.exe".
references:
    - https://github.com/gabe-k/themebleed
    - Internal Research
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-09-18
tags:
    - attack.execution
    - attack.t1204.002
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith: '\rundll32.exe'
        ImageLoaded|startswith: '\\\\'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    Image|endswith: '\rundll32.exe'
    ImageLoaded|startswith: '\\\\'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`Image`	ends_with	`\rundll32.exe` corpus 94 (sigma 94)	`field:"Image" kind:ends_with value:"\rundll32.exe"`
`ImageLoaded`	starts_with	`\\\\` corpus 2 (sigma 1, splunk 1)	`field:"ImageLoaded" kind:starts_with value:"\\\\"`

Remote DLL Load Via Rundll32.EXE

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`