Potential ClickFix Execution Pattern - Registry

calendar Nov 21, 2025 · attack.execution attack.t1204.001  ·
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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.

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 1title: Potential ClickFix Execution Pattern - Registry
 2id: f5fe36cf-f1ec-4c23-903d-09a3110f6bbb
 3related:
 4    - id: d487ed4a-fd24-436d-a0b2-f4e95f7b2635
 5      type: similar
 6status: experimental
 7description: |
 8    Detects potential ClickFix malware execution patterns by monitoring registry modifications in RunMRU keys containing HTTP/HTTPS links.
 9    ClickFix is known to be distributed through phishing campaigns and uses techniques like clipboard hijacking and fake CAPTCHA pages.
10    Through the fakecaptcha pages, the adversary tricks users into opening the Run dialog box and pasting clipboard-hijacked content,
11    such as one-liners that execute remotely hosted malicious files or scripts.    
12references:
13    - https://github.com/JohnHammond/recaptcha-phish
14    - https://www.zscaler.com/blogs/security-research/deepseek-lure-using-captchas-spread-malware
15    - https://www.threatdown.com/blog/clipboard-hijacker-tries-to-install-a-trojan/
16    - https://app.any.run/tasks/5c16b4db-4b36-4039-a0ed-9b09abff8be2
17    - https://www.esentire.com/security-advisories/netsupport-rat-clickfix-distribution
18    - https://medium.com/@boutnaru/the-windows-foreniscs-journey-run-mru-run-dialog-box-most-recently-used-57375a02d724
19    - https://unit42.paloaltonetworks.com/preventing-clickfix-attack-vector/
20    - https://medium.com/@poudelswachchhanda123/preventing-lnk-and-fakecaptcha-threats-a-system-hardening-approach-2f7b7ed2e493
21author: Swachchhanda Shrawan Poudel (Nextron Systems)
22date: 2025-03-25
23tags:
24    - attack.execution
25    - attack.t1204.001
26logsource:
27    category: registry_set
28    product: windows
29detection:
30    selection_registry:
31        TargetObject|contains: '\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\RunMRU\'
32    selection_details:
33        Details|contains:
34            - 'http://'
35            - 'https://'
36    selection_susp_pattern:
37        - Details|contains:
38              # Add more suspicious keywords
39              - 'account'
40              - 'anti-bot'
41              - 'botcheck'
42              - 'captcha'
43              - 'challenge'
44              - 'confirmation'
45              - 'fraud'
46              - 'human'
47              - 'identificator'
48              - 'identity'
49              - 'robot'
50              - 'validation'
51              - 'verification'
52              - 'verify'
53        - Details|contains:
54              - '%comspec%'
55              - 'bitsadmin'
56              - 'certutil'
57              - 'cmd'
58              - 'cscript'
59              - 'curl'
60              - 'mshta'
61              - 'powershell'
62              - 'pwsh'
63              - 'regsvr32'
64              - 'rundll32'
65              - 'schtasks'
66              - 'wget'
67              - 'wscript'
68    condition: all of selection_*
69falsepositives:
70    - Legitimate applications using RunMRU with HTTP links
71level: high

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