Windows Defender Exclusion Reigstry Key - Write Access Requested

calendar Nov 15, 2023 · attack.defense_evasion attack.t1562.001  ·
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Detects write access requests to the Windows Defender exclusions registry keys. This could be an indication of an attacker trying to request a handle or access the object to write new exclusions in order to bypass security.

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 1title: Windows Defender Exclusion Reigstry Key - Write Access Requested
 2id: e9c8808f-4cfb-4ba9-97d4-e5f3beaa244d
 3related:
 4    - id: 46a68649-f218-4f86-aea1-16a759d81820
 5      type: derived
 6    - id: a33f8808-2812-4373-ae95-8cfb82134978
 7      type: derived
 8status: test
 9description: |
10        Detects write access requests to the Windows Defender exclusions registry keys. This could be an indication of an attacker trying to request a handle or access the object to write new exclusions in order to bypass security.
11references:
12    - https://www.bleepingcomputer.com/news/security/gootkit-malware-bypasses-windows-defender-by-setting-path-exclusions/
13author: '@BarryShooshooga, Nasreddine Bencherchali (Nextron Systems)'
14date: 2019/10/26
15modified: 2023/11/11
16tags:
17    - attack.defense_evasion
18    - attack.t1562.001
19logsource:
20    product: windows
21    service: security
22    definition: 'Requirements: Audit Policy : Security Settings/Local Policies/Audit Policy, Registry System Access Control (SACL): Auditing/User'
23detection:
24    selection:
25        AccessList|contains:
26            - '%%4417' # WriteData
27            - '%%4418' # AppendData
28        EventID:
29            - 4656 # A handle to an object was requested.
30            - 4663 # An attempt was made to access an object.
31        ObjectName|contains: '\Microsoft\Windows Defender\Exclusions\'
32    condition: selection
33falsepositives:
34    - Unknown
35level: medium

References

  • GootKit Malware Bypasses Windows Defender by Setting Path Exclusions

    As Windows Defender matures and becomes tightly integrated into Windows 10, malware writers are creating techniques to evade its detection. Such is the case with the GootKit banking Trojan, which use a UAC bypass and WMIC commands to exclude the malware executable from being scanned by Windows Defender Antivirus.


    Read More

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