Threat Description

Agent.AGW

Details

Aliases:Agent.AGW, Agent.AGW
Category:Malware
Type:Backdoor
Platform:W32

Summary



Agent.AGW is a backdoor program that allows contol over a victim's computers remotely by sending specific commands via IRC channels. This backdoor can also steal data, spread to a local network, and to computers vulnerable to exploits.



Removal


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.

More

You may wish to refer to the Support Community for further assistance. You also may also refer to General Removal Instructions for a general guide on alternative disinfection actions.



Technical Details



Agent.AGW is a backdoor program that allows control over a victim's computers remotely by sending specific commands via IRC channels. This backdoor can also steal data, spread to a local network, and to computers vulnerable to exploits.

Upon execution, it drops the following files:

  • %WinDir%\lsass.exe- a copy of itself.
  • %SysDir%\rdriv.sys- a trojan rootkit used to hide its presence on the machine. This is now detected as Rootkit.Win32.Agent.p.

Note: %WinDir%" represents the Windows root directory and "%SysDir%" represents the Windows System directory.

It installs itself as a service by creating the following registry keys:

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lsass]
  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\rdriv]

It installs itself as a service by creating the following registry keys:

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lsass]

It creates the following registry entries to lower the system's security settings:

  • [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center]UpdatesDisableNotify = "dword:00000000"AntiVirusDisableNotify = "dword:00000000"FirewallDisableNotify = "dword:0000000"AntiVirusOverride = "dword:00000000"FirewallOverride = "dword:00000000"
  • [HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate]DoNotAllowXPSP2 = dword:00000001
  • [HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\WindowsFirewall\DomainProfile]EnableFirewall = "dword:00000000"
  • [HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\WindowsFirewall\StandardProfile]EnableFirewall = "dword:00000000"

It creates the following registry entries to disable Administrative Shares in NT4.0 Server and Workstation:

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters]AutoShareWks = "dword:00000000"AutoShareServer = "dword:00000000"
  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanworkstation\parameters]AutoShareWks = "dword:00000000"AutoShareServer = "dword:00000000"

Agent.AGW also modifies the following registry entries to disable and restrict anonymous access and DCOM network binding:

  • [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Ole]EnableDCOM = "N"

Note: the default value is EnableDCOM = "Y".

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa]restrictanonymous = "dword:00000001"

Note: The default value for restrictanonymous is user dependent.

Agent.AGW also disables automatic update of Service Pack 2 in Windows XP by changing the following registry entry:

  • [HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate]DoNotAllowXPSP2 = "1"

Note: The default value for DoNotAllowXPSP2 = "0".

It modifies the following regsitry entry to shorten the waiting time for services to stop after service notification of system Shutdown:

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control]WaitToKillServiceTimeout= "7000"

Note: This is equivalent to 7 seconds. The default value is WaitToKillServiceTimeout= "20000", which is equivalent to 20 seconds.

It also disables the Messenger, Remote Registry, Security Center, and Telnet services respectively by modifiying the following regsitry entries:

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Messenger]Start = "dword:00000004"

Note: Default value is Start = "dword:00000002".

  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\RemoteRegistry]Start = "dword:00000004"

Note: Default value for Start = "dword:00000002".

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\wscsvc]Start = "dword:00000004"

Note: Default value is Start = "dword:00000002".

  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TlntSvr]Start = "dword:00000004"

Note: Default value is Start = "dword:00000003".

Agent.AGW attempts to connect to the following IRC server:

  • bla.girlsontheblock.com

It attempts to join the following IRC channels:

  • #na-e
  • #na-s

Once successfully connected, a hacker can send commands to the bots on the IRC channel to control the infected computer. It has the ability to do the following:

  • Display System Information
  • Download and Upload a File
  • List current processes
  • Scan for Files
  • Execute a file
  • Perform denial of service attack
  • Steal user information and log keyboard and mouse events
  • Send copies using different IM applications
  • Visit websites
  • Enumerate remote shares
  • Scan and exploit computers vulnerable to exploits

When spreading, the bot can exploit the following vulnerabilities:

  • Vulnerability in Plug and Play Could Allow Remote Code Execution and Elevation of Privilege (MS05-039) port 445
  • Vulnerability in Server Service Could Allow Remote Code Execution (MS06-040) port 139

It uses the following user accounts:

  • administrator
  • admin

- to connect to the target machine's hidden shares:

  • Admin$
  • ipc$

- by using the following list of weak passwords:

  • 12345
  • 123456
  • 654321
  • admin
  • asdfgh
  • server

It also tries to steal usernames and passwords from the following known applications:

  • MSN Hotmail
  • Outlook Express
  • PayPal


Detection



Detection Type: PC
Database: 2006-09-05_02




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