Windows Application Whitelisting Bypass Attempt via Rundll32

name: Windows Application Whitelisting Bypass Attempt via Rundll32
id: 1ef5dab0-e1f1-495d-a272-d134583c10b1
version: 6
creation_date: '2021-02-05'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: TTP
description: |
    The following analytic detects the execution of rundll32.exe calling one of the following DLLs:

    - Advpack.dll
    - Ieadvpack.dll
    - Syssetup.dll
    - Setupapi.dll

    with one of the following functions: "LaunchINFSection", "InstallHinfSection", "SetupInfObjectInstallAction".
    This method is identified through Endpoint Detection and Response (EDR) telemetry,
    focusing on command-line executions and process details.
    This activity is significant as it indicates a potential application
    control or whitelisting bypass, allowing script code execution from a file.
    If confirmed malicious, an attacker could execute arbitrary code, potentially leading to privilege escalation,
    persistence, or further network compromise.
    Investigate the script content, network connections, and any spawned child processes for further context.
data_source:
    - Sysmon EventID 1
    - Windows Event Log Security 4688
    - CrowdStrike ProcessRollup2
search: |
    | tstats `security_content_summariesonly`
      count min(_time) as firstTime
      max(_time) as lastTime
    from datamodel=Endpoint.Processes where
    `process_rundll32`
    Processes.process IN ("*syssetup*", "*advpack*", "*setupapi*")
    Processes.process IN ("*LaunchINFSection*", "*InstallHinfSection*", "*SetupInfObjectInstallAction*")
    NOT (Processes.parent_process_name="msiexec.exe" Processes.process="* C:\\Program Files (x86)\\Netskope\\EPDLP Deployment\\*")
    by Processes.action Processes.dest Processes.original_file_name Processes.parent_process
       Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id
       Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec
       Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level
       Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_application_whitelisting_bypass_attempt_via_rundll32_filter`
how_to_implement: |
    The detection is based on data that originates from Endpoint Detection
    and Response (EDR) agents. These agents are designed to provide security-related
    telemetry from the endpoints where the agent is installed. To implement this search,
    you must ingest logs that contain the process GUID, process name, and parent process.
    Additionally, you must ingest complete command-line executions.
    These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to
    the EDR product.
    The logs must also be mapped to the `Processes` node of the `Endpoint` data model.
    Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives: |
    Although unlikely, some legitimate applications may leverage one of the following DLLs syssetup.dll, dvpack.dll, ieadvpack.dll and can trigger a false positive. Apply additional filters as needed.
references:
    - https://attack.mitre.org/techniques/T1218/011/
    - https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1218.011/T1218.011.md
    - https://lolbas-project.github.io/lolbas/Binaries/Rundll32/
    - https://bohops.com/2018/02/26/leveraging-inf-sct-fetch-execute-techniques-for-bypass-evasion-persistence/
    - https://lolbas-project.github.io/lolbas/Libraries/Advpack/
    - https://lolbas-project.github.io/lolbas/Libraries/Ieadvpack/
    - https://lolbas-project.github.io/lolbas/Libraries/Setupapi/
    - https://lolbas-project.github.io/lolbas/Libraries/Syssetup/
drilldown_searches:
    - name: View the detection results for - "$user$" and "$dest$"
      search: '%original_detection_search% | search  user = "$user$" dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$" and "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
finding:
    title: An instance of $parent_process_name$ spawning $process_name$ loading syssetup.dll by calling the LaunchINFSection function on the command line was identified on endpoint $dest$ by user $user$.
    entity:
        field: user
        type: user
        score: 50
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 50
          message: An instance of $parent_process_name$ spawning $process_name$ loading syssetup.dll by calling the LaunchINFSection function on the command line was identified on endpoint $dest$ by user $user$.
threat_objects:
    - field: parent_process_name
      type: parent_process_name
    - field: process_name
      type: process_name
analytic_story:
    - Suspicious Rundll32 Activity
    - Living Off The Land
    - Compromised Windows Host
asset_type: Endpoint
mitre_attack_id:
    - T1218.011
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1218.011/atomic_red_team/windows-sysmon.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit