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Category: Malware

Type: Rootkit

Aliases: Rootkit:W32/Agent.UG, Worm.Win32.AutoRun.lyo


A program or set of programs which hides itself by subverting or evading the computer's security mechanisms, then allows remote users to secretly control the computer's operating system.


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

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About the product

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Technical Details

This rootkit will execute on the following operating systems:

  • Windows 2000
  • Windows XP
  • Windows 2003
  • Windows Vista
  • Windows Vista SP1

It removes the hooked addresses corresponding to the following NT Functions (which are implemented in Ntoskrnl.exe), then restores them to their original values:

  • NtProtectVirtualMemory
  • NtOpenThread
  • NtTerminateThread
  • NtCreatePort
  • NtConnectPort
  • NtCreateKey
  • NtAdjustPrivilegesToken
  • NtCreateFile
  • NtWriteVirtualMemory
  • NtOpenProcess
  • NtCreateProcess
  • NtCreateProcessEx
  • NtCreateSection
  • NtCreateThread
  • NtDeleteKey
  • NtDeleteValueKey
  • NtDuplicateObject
  • NtEnumerateKey
  • NtEnumerateValueKey
  • NtLoadDriver
  • NtLoadKey
  • NtLoadKey2
  • NtNotifyChangeKey
  • NtOpenFile
  • NtOpenKey
  • NtOpenSection
  • NtQueryKey
  • NtQueryMultipleValueKey
  • NtQueryValueKey
  • NtReplaceKey
  • NtRestoreKey
  • NtResumeThread
  • NtSaveKey
  • NtSetContextThread
  • NtSetInformationFile
  • NtSetInformationKey
  • NtSetSystemInformation
  • NtSetValueKey
  • NtSuspendThread
  • NtSystemDebugControl
  • NtTerminateProcess