Detection rules › Sigma

Potential Antivirus Software DLL Sideloading

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

Detects potential DLL sideloading of DLLs that are part of antivirus software suchas McAfee, Symantec...etc

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 7Image loaded

Rule body yaml

title: Potential Antivirus Software DLL Sideloading
id: 552b6b65-df37-4d3e-a258-f2fc4771ae54
status: test
description: Detects potential DLL sideloading of DLLs that are part of antivirus software suchas McAfee, Symantec...etc
references:
    - https://hijacklibs.net/ # For list of DLLs that could be sideloaded (search for dlls mentioned here in there)
author: Nasreddine Bencherchali (Nextron Systems), Wietze Beukema (project and research)
date: 2022-08-17
modified: 2025-10-07
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: image_load
    product: windows
detection:
    # Bitdefender
    selection_bitdefender:
        ImageLoaded|endswith: '\log.dll'
    filter_log_dll_bitdefender:
        ImageLoaded|startswith:
            - 'C:\Program Files\Bitdefender Antivirus Free\'
            - 'C:\Program Files (x86)\Bitdefender Antivirus Free\'
    filter_log_dll_dell_sar:
        Image: 'C:\Program Files\Dell\SARemediation\audit\TelemetryUtility.exe'
        ImageLoaded:
            - 'C:\Program Files\Dell\SARemediation\plugin\log.dll'
            - 'C:\Program Files\Dell\SARemediation\audit\log.dll'
    filter_log_dll_canon:
        ImageLoaded|startswith: 'C:\Program Files\Canon\MyPrinter\'
    filter_log_dll_avast:
        ImageLoaded:
            - 'C:\Program Files\AVAST Software\Avast\log.dll'
            - 'C:\Program Files (x86)\AVAST Software\Avast\log.dll'
    filter_log_dll_avg:
        ImageLoaded:
            - 'C:\Program Files\AVG\Antivirus\log.dll'
            - 'C:\Program Files (x86)\AVG\Antivirus\log.dll'
    # F-Secure
    selection_fsecure:
        ImageLoaded|endswith: '\qrt.dll'
    filter_fsecure:
        ImageLoaded|startswith:
            - 'C:\Program Files\F-Secure\Anti-Virus\'
            - 'C:\Program Files (x86)\F-Secure\Anti-Virus\'
    # McAfee
    selection_mcafee:
        ImageLoaded|endswith:
            - '\ashldres.dll'
            - '\lockdown.dll'
            - '\vsodscpl.dll'
    filter_mcafee:
        ImageLoaded|startswith:
            - 'C:\Program Files\McAfee\'
            - 'C:\Program Files (x86)\McAfee\'
    # CyberArk
    selection_cyberark:
        ImageLoaded|endswith: '\vftrace.dll'
    filter_cyberark:
        ImageLoaded|startswith:
            - 'C:\Program Files\CyberArk\Endpoint Privilege Manager\Agent\x32\'
            - 'C:\Program Files (x86)\CyberArk\Endpoint Privilege Manager\Agent\x32\'
    # Avast
    selection_avast:
        ImageLoaded|endswith: '\wsc.dll'
    filter_wsc_dll_avast:
        ImageLoaded|startswith:
            - 'C:\program Files\AVAST Software\Avast\'
            - 'C:\program Files (x86)\AVAST Software\Avast\'
    filter_wsc_dll_avg:
        ImageLoaded|startswith:
            - 'C:\Program Files\AVG\Antivirus\'
            - 'C:\Program Files (x86)\AVG\Antivirus\'
    # ESET
    selection_eset_deslock:
        ImageLoaded|endswith: '\DLPPREM32.dll'
    filter_eset_deslock:
        ImageLoaded|startswith:
            - 'C:\program Files\ESET'
            - 'C:\program Files (x86)\ESET'
    # Trend Micro Titanium
    selection_titanium:
        ImageLoaded|endswith: '\tmdbglog.dll'
    filter_titanium:
        ImageLoaded|startswith:
            - 'C:\program Files\Trend Micro\Titanium\'
            - 'C:\program Files (x86)\Trend Micro\Titanium\'
    condition: (selection_bitdefender and not 1 of filter_log_dll_*)
               or (selection_fsecure and not filter_fsecure)
               or (selection_mcafee and not filter_mcafee)
               or (selection_cyberark and not filter_cyberark)
               or (selection_avast and not 1 of filter_wsc_dll_*)
               or (selection_titanium and not filter_titanium)
               or (selection_eset_deslock and not filter_eset_deslock)
falsepositives:
    - Applications that load the same dlls mentioned in the detection section. Investigate them and filter them out if a lot FPs are caused.
    - Dell SARemediation plugin folder (C:\Program Files\Dell\SARemediation\plugin\log.dll) is known to contain the 'log.dll' file.
    - The Canon MyPrinter folder 'C:\Program Files\Canon\MyPrinter\' is known to contain the 'log.dll' file
level: medium

Stages and Predicates

Stage 0: condition

(selection_bitdefender and not 1 of filter_log_dll_*)

Stage 1: selection_bitdefender

selection_bitdefender:
    ImageLoaded|endswith: '\log.dll'

Stage 2: not filter_log_dll_*

filter_log_dll_bitdefender:
    ImageLoaded|startswith:
        - 'C:\Program Files\Bitdefender Antivirus Free\'
        - 'C:\Program Files (x86)\Bitdefender Antivirus Free\'
filter_log_dll_dell_sar:
    Image: 'C:\Program Files\Dell\SARemediation\audit\TelemetryUtility.exe'
    ImageLoaded:
        - 'C:\Program Files\Dell\SARemediation\plugin\log.dll'
        - 'C:\Program Files\Dell\SARemediation\audit\log.dll'
filter_log_dll_canon:
    ImageLoaded|startswith: 'C:\Program Files\Canon\MyPrinter\'
filter_log_dll_avast:
    ImageLoaded:
        - 'C:\Program Files\AVAST Software\Avast\log.dll'
        - 'C:\Program Files (x86)\AVAST Software\Avast\log.dll'
filter_log_dll_avg:
    ImageLoaded:
        - 'C:\Program Files\AVG\Antivirus\log.dll'
        - 'C:\Program Files (x86)\AVG\Antivirus\log.dll'

Stage 3: selection_fsecure

selection_fsecure:
    ImageLoaded|endswith: '\qrt.dll'

Stage 4: not filter_fsecure

filter_fsecure:
    ImageLoaded|startswith:
        - 'C:\Program Files\F-Secure\Anti-Virus\'
        - 'C:\Program Files (x86)\F-Secure\Anti-Virus\'

Stage 5: selection_mcafee

selection_mcafee:
    ImageLoaded|endswith:
        - '\ashldres.dll'
        - '\lockdown.dll'
        - '\vsodscpl.dll'

Stage 6: not filter_mcafee

filter_mcafee:
    ImageLoaded|startswith:
        - 'C:\Program Files\McAfee\'
        - 'C:\Program Files (x86)\McAfee\'

Stage 7: selection_cyberark

selection_cyberark:
    ImageLoaded|endswith: '\vftrace.dll'

Stage 8: not filter_cyberark

filter_cyberark:
    ImageLoaded|startswith:
        - 'C:\Program Files\CyberArk\Endpoint Privilege Manager\Agent\x32\'
        - 'C:\Program Files (x86)\CyberArk\Endpoint Privilege Manager\Agent\x32\'

Stage 9: selection_avast

selection_avast:
    ImageLoaded|endswith: '\wsc.dll'

Stage 10: not filter_wsc_dll_*

filter_wsc_dll_avast:
    ImageLoaded|startswith:
        - 'C:\program Files\AVAST Software\Avast\'
        - 'C:\program Files (x86)\AVAST Software\Avast\'
filter_wsc_dll_avg:
    ImageLoaded|startswith:
        - 'C:\Program Files\AVG\Antivirus\'
        - 'C:\Program Files (x86)\AVG\Antivirus\'

Stage 11: selection_titanium

selection_titanium:
    ImageLoaded|endswith: '\tmdbglog.dll'

Stage 12: not filter_titanium

filter_titanium:
    ImageLoaded|startswith:
        - 'C:\program Files\Trend Micro\Titanium\'
        - 'C:\program Files (x86)\Trend Micro\Titanium\'

Stage 13: selection_eset_deslock

selection_eset_deslock:
    ImageLoaded|endswith: '\DLPPREM32.dll'

Stage 14: not filter_eset_deslock

filter_eset_deslock:
    ImageLoaded|startswith:
        - 'C:\program Files\ESET'
        - 'C:\program Files (x86)\ESET'

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
ImageLoadedeqC:\Program Files\Dell\SARemediation\audit\log.dll
ImageLoadedeqC:\Program Files\Dell\SARemediation\plugin\log.dll
ImageeqC:\Program Files\Dell\SARemediation\audit\TelemetryUtility.exe
ImageLoadedeqC:\Program Files (x86)\AVAST Software\Avast\log.dll
ImageLoadedeqC:\Program Files (x86)\AVG\Antivirus\log.dll
ImageLoadedeqC:\Program Files\AVAST Software\Avast\log.dll
ImageLoadedeqC:\Program Files\AVG\Antivirus\log.dll
ImageLoadedstarts_withC:\Program Files (x86)\Bitdefender Antivirus Free\
ImageLoadedstarts_withC:\Program Files\Bitdefender Antivirus Free\
ImageLoadedstarts_withC:\Program Files\Canon\MyPrinter\
ImageLoadedstarts_withC:\Program Files (x86)\F-Secure\Anti-Virus\
ImageLoadedstarts_withC:\Program Files\F-Secure\Anti-Virus\
ImageLoadedstarts_withC:\Program Files (x86)\McAfee\
ImageLoadedstarts_withC:\Program Files\McAfee\
ImageLoadedstarts_withC:\Program Files (x86)\CyberArk\Endpoint Privilege Manager\Agent\x32\
ImageLoadedstarts_withC:\Program Files\CyberArk\Endpoint Privilege Manager\Agent\x32\
ImageLoadedstarts_withC:\Program Files (x86)\AVG\Antivirus\
ImageLoadedstarts_withC:\Program Files\AVG\Antivirus\
ImageLoadedstarts_withC:\program Files (x86)\AVAST Software\Avast\
ImageLoadedstarts_withC:\program Files\AVAST Software\Avast\
ImageLoadedstarts_withC:\program Files (x86)\Trend Micro\Titanium\
ImageLoadedstarts_withC:\program Files\Trend Micro\Titanium\
ImageLoadedstarts_withC:\program Files (x86)\ESET
ImageLoadedstarts_withC:\program Files\ESET

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
ImageLoadedends_with
  • \DLPPREM32.dll
  • \ashldres.dll
  • \lockdown.dll
  • \log.dll
  • \qrt.dll
  • \tmdbglog.dll
  • \vftrace.dll
  • \vsodscpl.dll
  • \wsc.dll