WORM_IRCBOT.AJG
Trojan:Win32/Ircbrute (Microsoft), W32/IRCBot.gen.cq (McAfee), a variant of Win32/Injector.VID trojan (ESET), W32.IRCBot (Symantec)
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Worm
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
This worm arrives by connecting affected removable drives to a system. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
TECHNICAL DETAILS
Arrival Details
This worm arrives by connecting affected removable drives to a system.
It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Installation
This worm drops the following copies of itself into the affected system and executes them:
- %System%\igfxud64.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Intel Software Updater = "%System%\igfxud64.exe"
Other System Modifications
This worm adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\AppCompatFlags
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\AppCompatFlags\
Layers
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\AppCompatFlags\
Layers
%System%\igfxud64.exe = "DisableNXShowUI"
It creates the following registry entry(ies) to bypass Windows Firewall:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%System%\igfxud64.exe = "%System%\igfxud64.exe:*:Enabled:Intel Software Updater"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\igfxud64.exe = "%System%\igfxud64.exe:*:Enabled:Intel Software Updater"
Propagation
This worm creates the following folders in all removable drives:
- {Drive Letter}:\~Restore.{645ff040-5081-101b-9f08-00aa002f954e}
It drops the following copy(ies) of itself in all removable drives:
- {Drive Letter}:\~Restore.{645ff040-5081-101b-9f08-00aa002f954e}\res-p0391726.id
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
The said .INF file contains the following strings:
;{garbage}
[Autorun]
;{garbage}
open=CMD /C START ~Restore.{645ff040-5081-101b-9f08-00aa002f954e}\res-p0391726.id
;{garbage}
icon=%windir%\system32\SHELL32.dll,3
;{garbage}
action=Open device to locate files.
;{garbage}
shell\open=Open
;{garbage}
shell\open\command=CMD /C START ~Restore.{645ff040-5081-101b-9f08-00aa002f954e}\res-p0391726.id
;{garbage}
shell\explore=Explore
;{garbage}
shell\explore\command=CMD /C START ~Restore.{645ff040-5081-101b-9f08-00aa002f954e}\res-p0391726.id
;{garbage}
shell\search=Search...
;{garbage}
shell\search\command=CMD /C START ~Restore.{645ff040-5081-101b-9f08-00aa002f954e}\res-p0391726.id
;{garbage}
useautoplay=1
Other Details
This worm connects to the following possibly malicious URL:
- {BLOCKED}-90-02.{BLOCKED}-co2-as86409.su
- {BLOCKED}155.{BLOCKED}4-c01-as86179.su
- {BLOCKED}-170.{BLOCKED}4-c01-as86179.su
- {BLOCKED}162.{BLOCKED}4-c01-as86179.su
- {BLOCKED}-98-06.{BLOCKED}-co2-as86409.su
SOLUTION
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Restart in Safe Mode
Step 3
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion
- AppCompatFlags
- AppCompatFlags
Step 4
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- Intel Software Updater = "%System%\igfxud64.exe"
- Intel Software Updater = "%System%\igfxud64.exe"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\DomainProfile\AuthorizedApplications\List
- %System%\igfxud64.exe = "%System%\igfxud64.exe:*:Enabled:Intel Software Updater"
- %System%\igfxud64.exe = "%System%\igfxud64.exe:*:Enabled:Intel Software Updater"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- %System%\igfxud64.exe = "%System%\igfxud64.exe:*:Enabled:Intel Software Updater"
- %System%\igfxud64.exe = "%System%\igfxud64.exe:*:Enabled:Intel Software Updater"
Step 5
Search and delete this folder
- {Drive Letter}:\~Restore.{645ff040-5081-101b-9f08-00aa002f954e}
Step 6
Search and delete AUTORUN.INF files created by WORM_IRCBOT.AJG that contain these strings
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_IRCBOT.AJG. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
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