Katz Stealer DLL Loaded

SIGMA detection rule by Swachchhanda Shrawan Poudel (Nextron Systems) · NOASSERTION

Detects loading of DLLs associated with Katz Stealer malware 2025 variants. Katz Stealer is a malware variant that is known to be used for stealing sensitive information from compromised systems. The process that loads these DLLs are very likely to be malicious.

title: Katz Stealer DLL Loaded
id: e6c7ab7c-c79d-4b84-b913-b2ec3f8e8a98
status: experimental
description: |
    Detects loading of DLLs associated with Katz Stealer malware 2025 variants.
    Katz Stealer is a malware variant that is known to be used for stealing sensitive information from compromised systems.
    The process that loads these DLLs are very likely to be malicious.
references:
    - Internal Research
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-05-22
tags:
    - attack.execution
    - attack.t1129
    - detection.emerging-threats
logsource:
    category: image_load
    product: windows
detection:
    selection:
        ImageLoaded|endswith:
            - '\katz_ontop.dll'
            - '\AppData\Local\Temp\received_dll.dll'
    condition: selection
falsepositives:
    - Unlikely
level: high

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

80827f0c-74d3-487e-8820-eab7932cd971

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

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