Windows Process Creation: Elise backdoor-related DLL deletion and execution via svchost.exe

Alerts on svchost.exe process commands referencing cached NavShExt.dll deletion and execution markers consistent with Elise backdoor activity.

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windows-process-creation-elise-backdoor-related-dll-deletion-and-execution-via-s-e507feb7

title: "Windows Process Creation: Elise backdoor-related DLL deletion and execution via svchost.exe"
id: d1bacdb2-3f1b-4c44-87dc-67d259d2a8dd
status: test
description: This rule flags Windows process creation events involving svchost.exe where the command line references the NavShExt.dll cache path and includes patterns consistent with deleting and invoking that DLL (e.g., a cached DLL path ending and the function marker ",Setting"). Such behavior matters because malware often stages or removes components from user cache directories and then triggers execution through Windows host processes. The detection relies on process creation telemetry with Image and CommandLine fields.
references:
  - https://community.rsa.com/community/products/netwitness/blog/2018/02/13/lotus-blossom-continues-asean-targeting
  - https://web.archive.org/web/20200302083912/https://www.accenture.com/t20180127T003755Z_w_/us-en/_acnmedia/PDF-46/Accenture-Security-Dragonfish-Threat-Analysis.pdf
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2018/Malware/Elise-Backdoor/proc_creation_win_malware_elise.yml
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2018-01-31
modified: 2023-03-09
tags:
  - attack.g0030
  - attack.g0050
  - attack.s0081
  - attack.execution
  - attack.t1059.003
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection_other_svchost:
    Image|endswith: \Microsoft\Network\svchost.exe
  selection_other_del:
    CommandLine|contains|all:
      - \Windows\Caches\NavShExt.dll
      - /c del
  selection_dll_path:
    CommandLine|endswith:
      - \AppData\Roaming\MICROS~1\Windows\Caches\NavShExt.dll
      - \AppData\Roaming\Microsoft\Windows\Caches\NavShExt.dll
  selection_dll_function:
    CommandLine|contains: ",Setting"
  condition: 1 of selection_other_* or all of selection_dll_*
falsepositives:
  - Unlikely
level: critical
license: DRL-1.1
related:
  - id: e507feb7-5f73-4ef6-a970-91bb6f6d744f
    type: derived

What it detects

This rule flags Windows process creation events involving svchost.exe where the command line references the NavShExt.dll cache path and includes patterns consistent with deleting and invoking that DLL (e.g., a cached DLL path ending and the function marker ",Setting"). Such behavior matters because malware often stages or removes components from user cache directories and then triggers execution through Windows host processes. The detection relies on process creation telemetry with Image and CommandLine fields.

Known false positives

Unlikely

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.