WORM_LINEAGE.OI
Windows 2000, XP, Server 2003

Threat Type: Worm
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Propagates via removable drives
This worm adds registry entries to enable its automatic execution at every system startup.
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
116,290 bytes
PE
Yes
17 Jul 2009
Drops files
Installation
This worm drops the following files:
- %System%\kavo.exe - copy of itself
- %System%\kavo0.dll - detected as MAL_NSANTI-1
- %User Temp%\5.dll - detected as MAL_NSANTI-1
(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.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)
It injects threads into the following normal process(es):
- explorer.exe
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
kava = %System%\kavo.exe
Other System Modifications
This worm modifies the following registry entries to hide files with Hidden attributes:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = 2
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = 0
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
SHOWALL
CheckedValue = 0
(Note: The default value data of the said registry entry is 1.)
Propagation
This worm drops the following copy(ies) of itself in all removable drives:
- u.cmd
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 characters}
[AutoRun]
;{garbage characters}
open=u.cmd
;{garbage characters}
shell\open\Command=u.cmd
;{garbage characters}
shell\open\Default=1
;{garbage characters}
shell\explore\Command=u.cmd
;{garbage characters}
SOLUTION
8.900
5.150.05
10 Mar 2008
5.151.00
10 Mar 2010
Step 1
For Windows ME and XP users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 3
Restart in Safe Mode
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- kava = %System%\kavo.exe
- kava = %System%\kavo.exe
Step 5
Restore this modified 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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: Hidden = 2
To: Hidden = 1
- From: Hidden = 2
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: ShowSuperHidden = 0
To: ShowSuperHidden = 1
- From: ShowSuperHidden = 0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL
- From: CheckedValue = 0
To: CheckedValue = 1
- From: CheckedValue = 0
Step 6
Search and delete AUTORUN.INF files created by WORM_LINEAGE.OI that contain these strings
;{garbage characters}
[AutoRun]
;{garbage characters}
open=u.cmd
;{garbage characters}
shell\open\Command=u.cmd
;{garbage characters}
shell\open\Default=1
;{garbage characters}
shell\explore\Command=u.cmd
;{garbage characters}
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_LINEAGE.OI 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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