Detection rules › Sigma

Potential DLL Sideloading Of KeyScramblerIE.DLL Via KeyScrambler.EXE

Status
test
Severity
high
Log source
product windows, category image_load
Author
Swachchhanda Shrawan Poudel
Source
github.com/SigmaHQ/sigma

Detects potential DLL side loading of "KeyScramblerIE.dll" by "KeyScrambler.exe". Various threat actors and malware have been found side loading a masqueraded "KeyScramblerIE.dll" through "KeyScrambler.exe".

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 7Image loaded

Rule body yaml

title: Potential DLL Sideloading Of KeyScramblerIE.DLL Via KeyScrambler.EXE
id: d2451be2-b582-4e15-8701-4196ac180260
related:
    - id: ca5583e9-8f80-46ac-ab91-7f314d13b984
      type: similar
status: test
description: |
    Detects potential DLL side loading of "KeyScramblerIE.dll" by "KeyScrambler.exe".
    Various threat actors and malware have been found side loading a masqueraded "KeyScramblerIE.dll" through "KeyScrambler.exe".
references:
    - https://thehackernews.com/2024/03/two-chinese-apt-groups-ramp-up-cyber.html
    - https://csirt-cti.net/2024/02/01/stately-taurus-continued-new-information-on-cyberespionage-attacks-against-myanmar-military-junta/
    - https://bazaar.abuse.ch/sample/5cb9876681f78d3ee8a01a5aaa5d38b05ec81edc48b09e3865b75c49a2187831/
    - https://twitter.com/Max_Mal_/status/1775222576639291859
    - https://twitter.com/DTCERT/status/1712785426895839339
author: Swachchhanda Shrawan Poudel
date: 2024-04-15
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith:
            - '\KeyScrambler.exe'
            - '\KeyScramblerLogon.exe'
        ImageLoaded|endswith: '\KeyScramblerIE.dll'
    filter_main_legitimate_path:
        Image|contains:
            - 'C:\Program Files (x86)\KeyScrambler\'
            - 'C:\Program Files\KeyScrambler\'
        ImageLoaded|contains:
            - 'C:\Program Files (x86)\KeyScrambler\'
            - 'C:\Program Files\KeyScrambler\'
    filter_main_signature:
        Signature: 'QFX Software Corporation'
        SignatureStatus: 'Valid'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    Image|endswith:
        - '\KeyScrambler.exe'
        - '\KeyScramblerLogon.exe'
    ImageLoaded|endswith: '\KeyScramblerIE.dll'

Stage 2: not filter_main_*

filter_main_legitimate_path:
    Image|contains:
        - 'C:\Program Files (x86)\KeyScrambler\'
        - 'C:\Program Files\KeyScrambler\'
    ImageLoaded|contains:
        - 'C:\Program Files (x86)\KeyScrambler\'
        - 'C:\Program Files\KeyScrambler\'
filter_main_signature:
    Signature: 'QFX Software Corporation'
    SignatureStatus: 'Valid'

Exclusions

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

FieldKindExcluded values
ImagematchC:\Program Files (x86)\KeyScrambler\
ImagematchC:\Program Files\KeyScrambler\
ImageLoadedmatchC:\Program Files (x86)\KeyScrambler\
ImageLoadedmatchC:\Program Files\KeyScrambler\
SignatureeqQFX Software Corporation
SignatureStatuseqValid

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
Imageends_with
  • \KeyScrambler.exe
  • \KeyScramblerLogon.exe corpus 2 (sigma 2)
ImageLoadedends_with
  • \KeyScramblerIE.dll