Suspicious Windows Defender Registry Key Tampering Via Reg.EXE

Detects the usage of "reg.exe" to tamper with different Windows Defender registry keys in order to disable some important features related to protection and detection

Sigma rule (View on GitHub)

 1title: Suspicious Windows Defender Registry Key Tampering Via Reg.EXE
 2id: 452bce90-6fb0-43cc-97a5-affc283139b3
 3status: test
 4description: Detects the usage of "reg.exe" to tamper with different Windows Defender registry keys in order to disable some important features related to protection and detection
 5references:
 6    - https://thedfirreport.com/2022/03/21/apt35-automates-initial-access-using-proxyshell/
 7    - https://github.com/swagkarna/Defeat-Defender-V1.2.0
 8    - https://www.elevenforum.com/t/video-guide-how-to-completely-disable-microsoft-defender-antivirus.14608/page-2
 9author: Florian Roth (Nextron Systems), Swachchhanda Shrawan Poudel, Nasreddine Bencherchali (Nextron Systems)
10date: 2022/03/22
11modified: 2023/06/05
12tags:
13    - attack.defense_evasion
14    - attack.t1562.001
15logsource:
16    category: process_creation
17    product: windows
18detection:
19    selection_root_img:
20        - Image|endswith: '\reg.exe'
21        - OriginalFileName: 'reg.exe'
22    selection_root_path:
23        CommandLine|contains:
24            - 'SOFTWARE\Microsoft\Windows Defender\'
25            - 'SOFTWARE\Policies\Microsoft\Windows Defender Security Center'
26            - 'SOFTWARE\Policies\Microsoft\Windows Defender\'
27    selection_dword_0:
28        CommandLine|contains|all:
29            - ' add '
30            - 'd 0'
31        CommandLine|contains:
32            - 'DisallowExploitProtectionOverride'
33            - 'EnableControlledFolderAccess'
34            - 'MpEnablePus'
35            - 'PUAProtection'
36            - 'SpynetReporting'
37            - 'SubmitSamplesConsent'
38            - 'TamperProtection'
39    selection_dword_1:
40        CommandLine|contains|all:
41            - ' add '
42            - 'd 1'
43        CommandLine|contains:
44            - 'DisableAntiSpyware'
45            - 'DisableAntiSpywareRealtimeProtection'
46            - 'DisableAntiVirus'
47            - 'DisableArchiveScanning'
48            - 'DisableBehaviorMonitoring'
49            - 'DisableBlockAtFirstSeen'
50            - 'DisableConfig'
51            - 'DisableEnhancedNotifications'
52            - 'DisableIntrusionPreventionSystem'
53            - 'DisableIOAVProtection'
54            - 'DisableOnAccessProtection'
55            - 'DisablePrivacyMode'
56            - 'DisableRealtimeMonitoring'
57            - 'DisableRoutinelyTakingAction'
58            - 'DisableScanOnRealtimeEnable'
59            - 'DisableScriptScanning'
60            - 'Notification_Suppress'
61            - 'SignatureDisableUpdateOnStartupWithoutEngine'
62    condition: all of selection_root_* and 1 of selection_dword_*
63falsepositives:
64    - Rare legitimate use by administrators to test software (should always be investigated)
65level: high

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