title: Potential ClickFix Execution Pattern - Registry
id: f5fe36cf-f1ec-4c23-903d-09a3110f6bbb
related:
- id: d487ed4a-fd24-436d-a0b2-f4e95f7b2635
type: similar
status: experimental
description: |
Detects potential ClickFix malware execution patterns by monitoring registry modifications in RunMRU keys containing HTTP/HTTPS links.
ClickFix is known to be distributed through phishing campaigns and uses techniques like clipboard hijacking and fake CAPTCHA pages.
Through the fakecaptcha pages, the adversary tricks users into opening the Run dialog box and pasting clipboard-hijacked content,
such as one-liners that execute remotely hosted malicious files or scripts.
references:
- https://github.com/JohnHammond/recaptcha-phish
- https://www.zscaler.com/blogs/security-research/deepseek-lure-using-captchas-spread-malware
- https://www.threatdown.com/blog/clipboard-hijacker-tries-to-install-a-trojan/
- https://app.any.run/tasks/5c16b4db-4b36-4039-a0ed-9b09abff8be2
- https://www.esentire.com/security-advisories/netsupport-rat-clickfix-distribution
- https://medium.com/@boutnaru/the-windows-foreniscs-journey-run-mru-run-dialog-box-most-recently-used-57375a02d724
- https://unit42.paloaltonetworks.com/preventing-clickfix-attack-vector/
- https://medium.com/@poudelswachchhanda123/preventing-lnk-and-fakecaptcha-threats-a-system-hardening-approach-2f7b7ed2e493
- https://www.scpx.com.au/2025/11/16/decades-old-finger-protocol-abused-in-clickfix-malware-attacks/
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-03-25
modified: 2025-11-19
tags:
- attack.execution
- attack.t1204.001
logsource:
category: registry_set
product: windows
detection:
selection_registry:
TargetObject|contains: '\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\RunMRU\'
selection_details:
Details|contains:
- 'http://'
- 'https://'
selection_susp_pattern:
- 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:
- Legitimate applications using RunMRU with HTTP links
level: high
title: Suspicious ClickFix/FileFix Execution Pattern
id: d487ed4a-fd24-436d-a0b2-f4e95f7b2635
related:
- id: f5fe36cf-f1ec-4c23-903d-09a3110f6bbb
type: similar
status: experimental
description: |
Detects suspicious execution patterns where users are tricked into running malicious commands via clipboard manipulation, either through the Windows Run dialog (ClickFix) or File Explorer address bar (FileFix).
Attackers leverage social engineering campaigns—such as fake CAPTCHA challenges or urgent alerts—encouraging victims to paste clipboard contents, often executing mshta.exe, powershell.exe, or similar commands to infect systems.
references:
- https://github.com/JohnHammond/recaptcha-phish
- https://www.zscaler.com/blogs/security-research/deepseek-lure-using-captchas-spread-malware
- https://www.threatdown.com/blog/clipboard-hijacker-tries-to-install-a-trojan/
- https://app.any.run/tasks/5c16b4db-4b36-4039-a0ed-9b09abff8be2
- https://www.esentire.com/security-advisories/netsupport-rat-clickfix-distribution
- https://www.scpx.com.au/2025/11/16/decades-old-finger-protocol-abused-in-clickfix-malware-attacks/ # filefix variant
author: montysecurity, Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-11-19
tags:
- attack.execution
- attack.t1204.001
- attack.t1204.004
logsource:
category: process_creation
product: windows
detection:
selection_parent:
ParentImage|endswith: '\explorer.exe'
CommandLine|contains: '#'
selection_cli_captcha:
CommandLine|contains:
- 'account'
- 'anti-bot'
- 'botcheck'
- 'captcha'
- 'challenge'
- 'confirmation'
- 'fraud'
- 'human'
- 'identification'
- 'identificator'
- 'identity'
- 'robot'
- 'validation'
- 'verification'
- 'verify'
condition: all of selection_*
falsepositives:
- Unlikely
level: high
title: Symlink Etc Passwd
id: c67fc22a-0be5-4b4f-aad5-2b32c4b69523
status: test
description: Detects suspicious command lines that look as if they would create symbolic links to /etc/passwd
references:
- https://www.qualys.com/2021/05/04/21nails/21nails.txt
author: Florian Roth (Nextron Systems)
date: 2019-04-05
modified: 2021-11-27
tags:
- attack.t1204.001
- attack.execution
logsource:
product: linux
detection:
keywords:
- 'ln -s -f /etc/passwd'
- 'ln -s /etc/passwd'
condition: keywords
falsepositives:
- Unknown
level: high
title: Suspicious Execution via macOS Script Editor
id: 6e4dcdd1-e48b-42f7-b2d8-3b413fc58cb4
status: test
description: Detects when the macOS Script Editor utility spawns an unusual child process.
author: Tim Rauch (rule), Elastic (idea)
references:
- https://github.com/elastic/protections-artifacts/commit/746086721fd385d9f5c6647cada1788db4aea95f#diff-7f541fbc4a4a28a92970e8bf53effea5bd934604429112c920affb457f5b2685
- https://wojciechregula.blog/post/macos-red-teaming-initial-access-via-applescript-url/
date: 2022-10-21
modified: 2022-12-28
logsource:
category: process_creation
product: macos
tags:
- attack.defense-impairment
- attack.t1566
- attack.t1566.002
- attack.initial-access
- attack.t1059
- attack.t1059.002
- attack.t1204
- attack.t1204.001
- attack.execution
- attack.persistence
- attack.t1553
detection:
selection_parent:
ParentImage|endswith: '/Script Editor'
selection_img:
- Image|endswith:
- '/curl'
- '/bash'
- '/sh'
- '/zsh'
- '/dash'
- '/fish'
- '/osascript'
- '/mktemp'
- '/chmod'
- '/php'
- '/nohup'
- '/openssl'
- '/plutil'
- '/PlistBuddy'
- '/xattr'
- '/sqlite'
- '/funzip'
- '/popen'
- Image|contains:
- 'python'
- 'perl'
condition: all of selection_*
falsepositives:
- Unknown
level: medium