Query: detect Detects when 'DllRegisterServer' is called in the commandline and the image is not rundll32. This could mean that the 'r in logs
Matching passage: Sigma rule: Detects when 'DllRegisterServer' is called in the commandline and the image is not rundll32. This could mean that the 'r. Logsource: windows / process_creation. Rule: title: Potential Renamed Rundll32 Execution id: 2569ed8c-1147-498a-9b8c-2ad3656b10ed related: - id: 0ba1da6d-b6ce-4366-828c-18826c9de23e type: derived status: test description: Detects when 'DllRegisterServer' is called in the commandline and the image is not rundll32. This could mean that the 'rundll32' utility has been renamed in order to avoid detection references: - https://twitter.com/swisscom_csirt/status/1331634525722521602?s=20 - https://app.any.run/tasks/f74c5157-8508-4ac6-9805-d63fe7b0d399/ author: Nasreddine Bencherchali (Nextron Systems) date: 2022-08-22 modified: 2023-02-03 tags: - attack.execution logsource: category: process_creation product: windows detection: selection: CommandLine|contains: DllRegisterServer filter: Image|endswith: \rundll32.exe condition: selection and not filter falsepositives: - Unlikely level: high
Near-miss passage: Sigma rule: Detects potential ClickFix malware execution patterns by monitoring registry modifications in RunMRU keys containing HTT. Logsource: windows / registry_set. Rule: 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: - 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