Detectionhightest

UAC Bypass Using Disk Cleanup

Detects the pattern of UAC Bypass using scheduled tasks and variable expansion of cleanmgr.exe (UACMe 34)

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Launch
Christian Burkard (Nextron Systems)Created Mon Aug 30Updated Sun Dec 01b697e69c-746f-4a86-9f59-7bfff8eab881windows
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic
Detection Logic1 selector
detection:
    selection:
        CommandLine|endswith: '"\system32\cleanmgr.exe /autoclean /d C:'
        ParentCommandLine: 'C:\Windows\system32\svchost.exe -k netsvcs -p -s Schedule'
        IntegrityLevel:
            - 'High'
            - 'System'
            - 'S-1-16-16384' # System
            - 'S-1-16-12288' # High
    condition: selection
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

Rule Metadata
Rule ID
b697e69c-746f-4a86-9f59-7bfff8eab881
Status
test
Level
high
Type
Detection
Created
Mon Aug 30
Modified
Sun Dec 01
Path
rules/windows/process_creation/proc_creation_win_uac_bypass_cleanmgr.yml
Raw Tags
attack.defense-evasionattack.privilege-escalationattack.t1548.002
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