Query: detect Detects the execution of "reg.exe" to alter registry keys that would replace the user's desktop background. This is a co in logs
Matching passage: Sigma rule: Detects the execution of "reg.exe" to alter registry keys that would replace the user's desktop background. This is a co. Logsource: windows / process_creation. Rule: title: Potentially Suspicious Desktop Background Change Using Reg.EXE id: 8cbc9475-8d05-4e27-9c32-df960716c701 related: - id: 85b88e05-dadc-430b-8a9e-53ff1cd30aae type: similar status: test description: 'Detects the execution of "reg.exe" to alter registry keys that would replace the user''s desktop background. This is a common technique used by malware to change the desktop background to a ransom note or other image. ' references: - https://www.attackiq.com/2023/09/20/emulating-rhysida/ - https://research.checkpoint.com/2023/the-rhysida-ransomware-activity-analysis-and-ties-to-vice-society/ - https://www.trendmicro.com/en_us/research/23/h/an-overview-of-the-new-rhysida-ransomware.html - https://www.virustotal.com/gui/file/a864282fea5a536510ae86c77ce46f7827687783628e4f2ceb5bf2c41b8cd3c6/behavior - https://admx.help/?Category=Windows_10_2016&Policy=Microsoft.Policies.WindowsDesktop::Wallpaper - https://admx.help/?Category=Windows_10_2016&Policy=Microsoft.Policies.ControlPanelDisplay::CPL_Personalization_NoDesktopBackgroundUI author: Stephen Lincoln @slincoln-aiq (AttackIQ) date: 2023-12-21 tags: - attack.persistence - attack.impact - attack.defense-impairment - attack.t1112 - attack.t1491.001 logsource: product: windows category: process_creation detection: selection_reg_img: - Image|endswith: \reg.exe - OriginalFileName: reg.exe selection_reg_flag: CommandLine|contains: add selection_keys: CommandLine|contains: - Control Panel\Desktop - CurrentVersion\Policies\ActiveDesktop - CurrentVersion\Policies\System selection_cli_reg_1: CommandLine|contains|all: - /v NoChangingWallpaper - /d 1 selection_cli_reg_2: CommandLine|contains|all: - /v Wallpaper - /t REG_SZ selection_cli_reg_3: CommandLine|contains|all: - /v WallpaperStyle - /d 2 condition: all of selection_reg_* and selection_keys and 1 of selection_cli_reg_* falsepositives: - Administrative scripts that change the desktop background to a company logo or other image. level: medium
Near-miss passage: Sigma rule: Detects LSASS process access for potential credential dumping by a Python-like tool such as LaZagne or Pypykatz.. Logsource: windows / process_access. Rule: title: Credential Dumping Activity By Python Based Tool id: f8be3e82-46a3-4e4e-ada5-8e538ae8b9c9 related: - id: 4b9a8556-99c4-470b-a40c-9c8d02c77ed0 type: obsolete - id: 7186e989-4ed7-4f4e-a656-4674b9e3e48b type: obsolete status: stable description: Detects LSASS process access for potential credential dumping by a Python-like tool such as LaZagne or Pypykatz. references: - https://twitter.com/bh4b3sh/status/1303674603819081728 - https://github.com/skelsec/pypykatz author: Bhabesh Raj, Jonhnathan Ribeiro date: 2023-11-27 modified: 2023-11-29 tags: - attack.credential-access - attack.t1003.001 - attack.s0349 logsource: category: process_access product: windows detection: selection: TargetImage|endswith: \lsass.exe CallTrace|contains|all: - _ctypes.pyd+ - :\Windows\System32\KERNELBASE.dll+ - :\Windows\SYSTEM32\ntdll.dll+ CallTrace|contains: - python27.dll+ - python3*.dll+ GrantedAccess: '0x1FFFFF' condition: selection falsepositives: - Unknown level: high