FileFix - Command Evidence in TypedPaths — Sigma Rule

Rule metadata and linked tags

Author: Alfie Champion (delivr.to), Swachchhanda Shrawan Poudel (Nextron Systems). Source status: experimental; severity: high. Source dates: 2025-07-05 / 2025-11-19.

{
  "category": "registry_set",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 65ee43c0a744c3409a6e314eb67421e864db3daacd822a42b81efefedf6d375e

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: FileFix - Command Evidence in TypedPaths
id: 4fee3d51-8069-4a4c-a0f7-924fcaff2c70
related:
    - id: 4be03877-d5b6-4520-85c9-a5911c0a656c
      type: similar
status: experimental
description: |
    Detects commonly-used chained commands and strings in the most recent 'url' value of the 'TypedPaths' key, which could be indicative of a user being targeted by the FileFix technique.
references:
    - https://x.com/russianpanda9xx/status/1940831134759506029
    - https://mrd0x.com/filefix-clickfix-alternative/
    - https://www.scpx.com.au/2025/11/16/decades-old-finger-protocol-abused-in-clickfix-malware-attacks/
author: Alfie Champion (delivr.to), Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-07-05
modified: 2025-11-19
tags:
    - attack.execution
    - attack.t1204.004
logsource:
    category: registry_set
    product: windows
detection:
    selection_base:
        TargetObject|endswith: '\Software\Microsoft\Windows\CurrentVersion\Explorer\TypedPaths\url1'
        Details|contains|all:
            - '#'
            - 'http'
    selection_cmd:
        - Details|contains:
              # Add more suspicious keywords
              - 'account'
              - 'anti-bot'
              - 'botcheck'
              - 'captcha'
              - 'challenge'
              - 'confirmation'
              - 'fraud'
              - 'human'
              - 'identification'
              - 'identificator'
              - 'identity'
              - 'robot'
              - 'validation'
              - 'verification'
              - 'verify'
        - Details|contains:
              - '%comspec%'
              - 'bitsadmin'
              - 'certutil'
              - 'cmd'
              - 'cscript'
              - 'curl'
              - 'finger'
              - 'mshta'
              - 'powershell'
              - 'pwsh'
              - 'regsvr32'
              - 'rundll32'
              - 'schtasks'
              - 'wget'
              - 'wscript'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://x.com/russianpanda9xx/status/1940831134759506029
• https://mrd0x.com/filefix-clickfix-alternative/
• https://www.scpx.com.au/2025/11/16/decades-old-finger-protocol-abused-in-clickfix-malware-attacks/