Query: rule covering Detects HTTP requests to low reputation TLDs (e.g. .xyz, .top, .ru) or ending in suspicious file extensions (.exe, .dll,
Matching passage: Sigma rule: Detects HTTP requests to low reputation TLDs (e.g. .xyz, .top, .ru) or ending in suspicious file extensions (.exe, .dll,. Logsource: zeek / http. Rule: title: HTTP Request to Low Reputation TLD or Suspicious File Extension id: 68c2c604-92ad-468b-bf4a-aac49adad08c status: experimental description: 'Detects HTTP requests to low reputation TLDs (e.g. .xyz, .top, .ru) or ending in suspicious file extensions (.exe, .dll, .hta), which may indicate malicious activity. ' references: - https://www.howtogeek.com/137270/50-file-extensions-that-are-potentially-dangerous-on-windows - https://www.spamhaus.org/reputation-statistics/cctlds/domains/ author: '@signalblur, Corelight' date: 2025-02-26 tags: - attack.initial-access - attack.command-and-control logsource: product: zeek service: http detection: selection_suspicious_tld: host|endswith: - .bid - .by - .cf - .click - .cm - .ga - .gq - .ir - .kp - .loan - .ml - .mm - .party - .pw - .ru - .su - .sy - .tk - .top - .tv - .ve - .work - .xyz selection_malicious_ext: uri|endswith: - .bat - .bin - .cmd - .cpl - .dll - .dylib - .elf - .exe - .hta - .iso - .jar - .js - .lnk - .msi - .pif - .ps1 - .py - .reg - .scr - .sh - .so - .vbs - .wsf selection_malicious_mime: resp_mime_types: - application/vnd.microsoft.portable-executable - application/x-bat - application/x-dosexec - application/x-elf - application/x-iso9660-image - application/x-java-archive - application/x-ms-shortcut - application/x-msdos-program - application/x-msdownload - application/x-python-code - application/x-sh condition: selection_suspicious_tld and 1 of selection_malicious_* falsepositives: - Rare legitimate software downloads from low quality TLDs level: medium
Near-miss passage: Sigma rule: Detects a potentially suspicious powershell script executions from temporary folder. Logsource: windows / process_creation. Rule: title: Potentially Suspicious Powershell Script Execution From Temp Folder id: a6a39bdb-935c-4f0a-ab77-35f4bbf44d33 status: test description: Detects a potentially suspicious powershell script executions from temporary folder references: - https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit/ author: Florian Roth (Nextron Systems), Max Altgelt (Nextron Systems), Tim Shelton date: 2021-07-14 modified: 2026-02-17 tags: - attack.execution - attack.t1059.001 logsource: category: process_creation product: windows detection: selection: Image|endswith: - \powershell.exe - \pwsh.exe CommandLine|contains: - \Windows\Temp - \Temporary Internet - \AppData\Local\Temp - \AppData\Roaming\Temp - '%TEMP%' - '%TMP%' - '%LocalAppData%\Temp' filter_optional_vscode: CommandLine|contains: -WindowStyle hidden -Verb runAs filter_optional_amazon_ec2: CommandLine|contains: \Windows\system32\config\systemprofile\AppData\Local\Temp\Amazon\EC2-Windows\ filter_optional_generic: CommandLine|contains: - ' >' - Out-File - ConvertTo-Json filter_optional_chocolatey_installer: ParentImage: - C:\Windows\System32\Msiexec.exe - C:\Windows\SysWOW64\Msiexec.exe Image|endswith: \powershell.exe CommandLine|contains|all: - -NoProfile -ExecutionPolicy Bypass -Command - AppData\Local\Temp\ - Install-Chocolatey.ps1 condition: selection and not 1 of filter_optional_* falsepositives: - Administrative scripts level: medium