Query: alert when Detects common commands used in Windows webshells
Matching passage: Sigma rule: Detects common commands used in Windows webshells. Logsource: webserver. Rule: title: Windows Webshell Strings id: 7ff9db12-1b94-4a79-ba68-a2402c5d6729 status: test description: Detects common commands used in Windows webshells references: - https://bad-jubies.github.io/RCE-NOW-WHAT/ - https://m365internals.com/2022/10/07/hunting-in-on-premises-exchange-server-logs/ author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems) date: 2017-02-19 modified: 2022-11-18 tags: - attack.persistence - attack.t1505.003 logsource: category: webserver detection: selection_method: cs-method: GET selection_keywords: - =whoami - =net%20user - =net+user - =net%2Buser - =cmd%20/c% - =cmd+/c+ - =cmd%2B/c% - =cmd%20/r% - =cmd+/r+ - =cmd%2B/r% - =cmd%20/k% - =cmd+/k+ - =cmd%2B/k% - =powershell% - =powershell+ - =tasklist% - =tasklist+ - =wmic% - =wmic+ - =ssh% - =ssh+ - =python% - =python+ - =python3% - =python3+ - =ipconfig - =wget% - =wget+ - =curl% - =curl+ - =certutil - =copy%20%5C%5C - =dsquery% - =dsquery+ - =nltest% - =nltest+ condition: all of selection_* falsepositives: - Web sites like wikis with articles on os commands and pages that include the os commands in the URLs - User searches in search boxes of the respective website 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