Query: detection rule: Detects suspicious user agent strings used in APT malware in proxy logs
Matching passage: Sigma rule: Detects suspicious user agent strings used in APT malware in proxy logs. Logsource: proxy. Rule: title: APT User Agent id: 6ec820f2-e963-4801-9127-d8b2dce4d31b status: test description: Detects suspicious user agent strings used in APT malware in proxy logs references: - Internal Research author: Florian Roth (Nextron Systems), Markus Neis date: 2019-11-12 modified: 2024-02-15 tags: - attack.command-and-control - attack.t1071.001 logsource: category: proxy detection: selection: c-useragent: - SJZJ (compatible; MSIE 6.0; Win32) - Mozilla/5.0 (Windows NT 6.; WOW64; rv:20.0) Gecko/20100101 Firefox/20.0 - 'User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC' - Mozilla/4.0 (compatible; MSIE 7.4; Win32;32-bit) - webclient - Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-EN; rv:1.7.12) Gecko/200 - Mozilla/4.0 (compatible; MSI 6.0; - Mozilla/5.0 (Windows NT 6.3; WOW64; rv:28.0) Gecko/20100101 Firefox/28.0 - Mozilla/5.0 (Windows NT 6.2; WOW64; rv:20.0) Gecko/20100101 Firefox/ - Mozilla/5.0 (Windows NT 6.; WOW64; rv:20.0) Gecko/20100101 Firefox/2 - Mozilla/4.0 - Netscape - Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-EN; rv:1.7.12) Gecko/20100719 Firefox/1.0.7 - Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Firefox/3.6.13 GTB7.1 - Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0) - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NETCLR 2.0.50727) - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; SV1) - Mozilla/4.0 (compatible; MSIE 11.0; Windows NT 6.1; SV1) - Mozilla/4.0 (compatible; MSIE 8.0; Win32) - Mozilla v5.1 (Windows NT 6.1; rv:6.0.1) Gecko/20100101 Firefox/6.0.1 - Mozilla/6.1 (compatible; MSIE 9.0; Windows NT 5.3; Trident/5.0) - Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648; InfoPath.1) - Mozilla/5.0 (Windows NT 6.1; WOW64) WinHttp/1.6.3.8 (WinHTTP/5.1) like Gecko - Mozilla v5.1 * - MSIE 8.0 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; InfoPath.2) - Mozilla/4.0 (compatible; RMS) - Mozilla/4.0 (compatible; MSIE 6.0; DynGate) - O/9.27 (W; U; Z) - Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.0; Trident/5.0; Trident/5.0* - Mozilla/5.0 (Windows NT 9; * - hots scot - Mozilla/5.0 (compatible; MSIE 10.0; Windows NT) - Mozilla/5.0 (Windows NT 6.1; WOW64) Chrome/28.0.1500.95 Safari/537.36 - Mozilla/5.0 (Windows NT 6.2; Win32; rv:47.0) - Mozilla/4.0 (compatibl
Near-miss passage: Sigma rule: Detects the image load of VSS DLL by uncommon executables. Logsource: windows / image_load. Rule: title: Suspicious Volume Shadow Copy Vssapi.dll Load id: 37774c23-25a1-4adb-bb6d-8bb9fd59c0f8 related: - id: 333cdbe8-27bb-4246-bf82-b41a0dca4b70 type: similar - id: 48bfd177-7cf2-412b-ad77-baf923489e82 type: similar status: test description: Detects the image load of VSS DLL by uncommon executables references: - https://github.com/ORCx41/DeleteShadowCopies author: frack113 date: 2022-10-31 modified: 2026-05-18 tags: - attack.impact - attack.t1490 logsource: category: image_load product: windows detection: selection: ImageLoaded|endswith: \vssapi.dll filter_main_windows: - Image: - C:\Windows\explorer.exe - C:\Windows\ImmersiveControlPanel\SystemSettings.exe - Image|startswith: - C:\Windows\System32\ - C:\Windows\SysWOW64\ - C:\Windows\Temp\{ - C:\Windows\WinSxS\ - C:\$WinREAgent\Scratch\ filter_main_program_files: Image|startswith: - C:\Program Files\ - C:\Program Files (x86)\ filter_main_null_image: Image: null filter_optional_programdata_packagecache: Image|startswith: C:\ProgramData\Package Cache\ filter_optional_avira: Image|contains|all: - \temp\is- - \avira_system_speedup.tmp condition: selection and not 1 of filter_main_* and not 1 of filter_optional_* falsepositives: - Unknown level: high