WORM_WINKO.AO

Malware type: Worm

Aliases: Worm.Win32.AutoRun.bnk (Kaspersky), W32/Winko.worm.dll (McAfee), W32.Kaxela.A (Symantec), TR/Autorun.CA (Avira), Mal/Heuri-E (Sophos), Backdoor:Win32/Popwin.gen!E (Microsoft)

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 98, ME, NT, 2000, XP, Server 2003

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:

High

Distribution potential:

High

Infection Channel 1 : Propagates via removable drives


Infection Channel 2 : Copies itself in all available physical drives


Description: 

This worm may be downloaded from remote sites by other malware. It may be dropped by other malware. It may also be downloaded unknowingly by a user when visiting malicious Web sites.

It creates registry entries to enable its automatic execution at every system startup. It registers itself as a system service to ensure its automatic execution at every system startup. It does this by creating registry entry

It creates and modifies registry entries as part of its installation routine. It also deletes a registry key.

It drops copies of itself in all physical drivesand in all removable drives. It drops an AUTORUN.INF file to automatically execute dropped copies when the drives are accessed.

It accesses Web sites to download files. As a result, malicious routines of the downloaded files may be exhibited on the affected system.

It drops component files.

For additional information about this threat, see:

Description created: Jan. 11, 2008 8:13:16 AM GMT -0800


TECHNICAL DETAILS


File type: PE

Memory resident:  Yes

Size of malware: 17,751 Bytes

Initial samples received on: Jan 7, 2008

Details:

Arrival Details

This worm may be downloaded from remote sites by other malware. It may be dropped by other malware. It may also be downloaded unknowingly by a user when visiting malicious Web sites.

Autostart Techniques

This worm creates the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
AVPSrv = "%Windows%\AVPSrv.exE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
cmdbcs = "%Windows%\cmdbcs.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
DbgHlp32 = "%Windows%\DbgHlp32.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
Kvsc3 = "%Windows%\Kvsc3.exE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
LotusHlp = "%Windows%\LotusHlp.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
mppds = "%Windows%\mppds.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
msccrt = "%Windows%\msccrt.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
MsIMMs32 = "%Windows%\MsIMMs32.exE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
MsPrint32D = "%Windows%\MsPrint32D.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
NAVMon32 = "%Windows%\NAVMon32.exE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
NVDispDrv = "%Windows%\NVDispDRV.EXE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
PTSShell = "%Windows%\PTSShell.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
RegSrv64D = "%Windows%\RegSrv64D.exE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
SHAProc = "%Windows%\SHAProc.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
upxdnd = "%Windows%\upxdnd.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
WinForm = "%Windows%\WinForm.exE"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
WinSysM = "%Windows%\371662M.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
WinSysW = "%Windows%\371662L.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Run
WSockDrv32 = "%Windows%\WSockDrv32.exe"

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

It registers itself as a system service to ensure its automatic execution at every system startup. It does this by creating the following registry key(s)/entry(ies):

HKEY_CURRENT_USER\SYSTEM\CurrentControlSet\Services\2C7E4380
Description = "93348300"
DisplayName = "2C7E4380"
ImagePath = "%System%\66857980.EXE -k"
ObjectName = "LocalSystem"

(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.)

Other System Modifications

This worm creates the following registry entry as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT
ReportBootOk = "1"

It modifies the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PCHealth\ErrorReporting
DoReport = "0"

(Note: The default value data for the said registry entry is 1.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PCHealth\ErrorReporting
ShowUI = "0"

(Note: The default value data for 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 for the said registry entry is 1.)

It deletes the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ERSv

This worm deletes itself after execution.

Propagation via Physical/Removable/Floppy Drives

This worm drops copies of itself in all physical drives and in all removable drives.

It drops an AUTORUN.INF file to automatically execute dropped copies when the drives are accessed. The file AUTORUN.INF contains the following strings:

[AutoRun]
open=auto.exe
shellexecute=auto.exe
shell\Auto\command=auto.exe

Download Routine

This worm accesses the following Web sites to download files:

  • http://{BLOCKED}wwool.cn/jt.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}wwool.cn/mh2.exe - detected as TSPY_ONLINEG.LPE
  • http://{BLOCKED}wwool.cn/tl0619.exe - detected as TSPY_ONLINEG.AXC
  • http://{BLOCKED}.189.{BLOCKED}.29/cq0619.exe - detected as TSPY_ONLINEG.AXC
  • http://{BLOCKED}.189.{BLOCKED}.29/dh0616.exe - detected as TSPY_ONLINEG.BUW
  • http://{BLOCKED}.189.{BLOCKED}.29/qqsg.exe - detected as TSPY_FRETHOG.OL
  • http://{BLOCKED}.189.{BLOCKED}.29/wow0617.exe- detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}.73.{BLOCKED}.201/mh0618.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}.73.{BLOCKED}.201/my0616.exe - detected as TSPY_ONLINEG.BUW
  • http://{BLOCKED}.73.{BLOCKED}.201/qj0617.exe - detected as TSPY_ONLINEG.AXJ
  • http://{BLOCKED}.73.{BLOCKED}.202/jh0619.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}.73.{BLOCKED}.202/wd0618.exe - detected as TSPY_ONLINEG.BUR
  • http://{BLOCKED}.73.{BLOCKED}.67/dh3.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}.73.{BLOCKED}.67/huaxia.exe - detected as TSPY_FRETHOG.NU
  • http://{BLOCKED}.73.{BLOCKED}.67/qqhx.exe - detected as TSPY_FRETHOG.NE
  • http://{BLOCKED}.73.{BLOCKED}.67/zt0616.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}.129.{BLOCKED}.132/fh.exe - detected as TSPY_FRETHOG.KH
  • http://{BLOCKED}.129.{BLOCKED}.132/jr.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}.129.{BLOCKED}.132/zy.exe - detected as TSPY_ONLINEG.NSM
  • http://{BLOCKED}lb.cn/soft//update.txt - text file that contains the download URLs of the downloaded malicios files.
  • http://{BLOCKED}lb.cn/soft/soft/e47e57844ef30ab4.exe - detected as TSPY_LEGMIR.CSF

Dropping Routine

This worm drops the following component files:

  • %System%\66857980.EXE - detected as WORM_WINKO.AO
  • %System%\93348300.DLL - detected as WORM_WINKO.AO
  • %System%\AVPSrv.dll - detected as TSPY_ONLINEG.AXC
  • %System%\cmdbcs.dll - detected as TSPY_ONLINEG.NSM
  • %System%\DbgHlp32.dll - detected as TSPY_ONLINEG.NSM
  • %System%\k98051577811.exe - detected as TSPY_LEGMIR.CSF
  • %System%\k98051579021.exe - detected as TSPY_LEGMIR.CTN
  • %System%\Kvsc3.dll - detected as TSPY_ONLINEG.AXJ
  • %System%\LotusHlp.dll - detected as TSPY_ONLINEG.BUI
  • %System%\LYLOADER.EXE - detected as TSPY_LOLYDA.J
  • %System%\LYMANGR.DLL - detected as TSPY_LOLYDA.J
  • %System%\mppds.dll - detected as TSPY_ONLINEG.NSM
  • %System%\msccrt.dll - detected as TSPY_FRETHOG.MU
  • %System%\MSDEG32.DLL - detected as TSPY_ONLINEG.BVC
  • %System%\MsIMMs32.dll - detected as TSPY_ONLINEG.BUR
  • %System%\MsPrint32D.dll - detected as TSPY_ONLINEG.BVE
  • %System%\NAVMon32.dll - detected as TSPY_ONLINEG.NSM
  • %System%\NVDispDrv.dll - detected as TSPY_ONLINEG.BUW
  • %System%\PTSShell.dll - detected as TSPY_ONLINEG.BVA
  • %System%\REGKEY.hiv - detected as TSPY_ONLINEG.OLS
  • %System%\RegSrv64D.dll - detected as TSPY_ONLINEG.NSM
  • %System%\SHAProc.dll - detected as TSPY_FRETHOG.OL
  • %System%\upxdnd.dll - detected as TSPY_ONLINEG.NSM
  • %System%\WinForm.dll - detected as TSPY_ONLINEG.NSM
  • %System%\WSockDrv32.dll - detected as TSPY_FRETHOG.NE
  • %User Profile%\Local Settings\Temp\LYLOADER.EXE - detected as TSPY_LOLYDA.J
  • %User Profile%\Local Settings\Temp\LYMANGR.DLL - detected as TSPY_LOLYDA.J
  • %User Profile%\Local Settings\Temp\MSDEG32.DLL - detected as TSPY_ONLINEG.BVC
  • %Windows%\371662MM.DLL - detected as TSPY_LEGMIR.FK
  • %Windows%\371662WL.DLL - detected as TSPY_LEGMIR.DAJ
  • %Windows%\AVPSrv.exE - detected as TSPY_ONLINEG.AXC
  • %Windows%\cmdbcs.exe - detected as TSPY_ONLINEG.NSM
  • %Windows%\DbgHlp32.exe - detected as TSPY_ONLINEG.NSM
  • %Windows%\Kvsc3.exE - detected as TSPY_ONLINEG.AXJ
  • %Windows%\LotusHlp.exe - detected as TSPY_ONLINEG.BUJ
  • %Windows%\mppds.exe - detected as TSPY_ONLINEG.NSM
  • %Windows%\msccrt.exe - detected as TSPY_FRETHOG.MU
  • %Windows%\MsIMMs32.exE - detected as TSPY_ONLINEG.BUR
  • %Windows%\MsPrint32D.exe - detected as TSPY_ONLINEG.BVF
  • %Windows%\NAVMon32.exE - detected as TSPY_ONLINEG.NSM
  • %Windows%\NVDispDRV.EXE - detected as TSPY_ONLINEG.BUW
  • %Windows%\PTSShell.exe - detected as TSPY_ONLINEG.BVB
  • %Windows%\RegSrv64D.exE - detected as TSPY_ONLINEG.NSM
  • %Windows%\SHAProc.exe - detected as TSPY_FRETHOG.NU
  • %Windows%\upxdnd.exe - detected as TSPY_ONLINEG.NSM
  • %Windows%\WinForm.exE - detected as TSPY_ONLINEG.NSM
  • %Windows%\WSockDrv32.exe - detected as TSPY_FRETHOG.KH

Affected Platforms

This worm runs on Windows 98, ME, NT, 2000, XP, and Server 2003.

Analysis By: Michael Cabel

Revision History:

First pattern file version: 4.942.13
First pattern file release date: Jan 11, 2008

SOLUTION


Minimum scan engine version needed: 8.300

Pattern file needed: 5.159.00

Pattern release date: Mar 12, 2008


Important note: The "Minimum scan engine" refers to the earliest Trend Micro scan engine version guaranteed to detect this threat. However, Trend Micro strongly recommends that you update to the latest version in order to get comprehensive protection. Download the latest scan engine here.

Solution:

Identifying the Malware Files

  1. Scan your computer with your Trend Micro antivirus product.
  2. Note the path and file name of all files detected as WORM_WINKO.AO.

Trend Micro customers need to download the latest virus pattern file before scanning their computer. Other users can use Housecall, the Trend Micro online threat scanner.

Important Windows ME/XP Cleaning Instructions

Users running Windows ME and XP must disable System Restore to allow full scanning of infected computers.

Users running other Windows versions can proceed with the succeeding solution set(s).

Restarting in Safe Mode

This malware has characteristics that require the computer to be restarted in safe mode. Go to this page for instructions on how to restart your computer in safe mode.

Removing Autostart Entries from the Registry

This solution deletes/modifies registry keys/entries added/modified by this malware. Before performing the steps below, make sure you know how to back up the registry and how to restore it if a problem occurs. Refer to this Microsoft article for more information about modifying your computer's registry.

  1. Open Registry Editor. Click Start>Run, type REGEDIT, then press Enter.
  2. In the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows>
    CurrentVersion>Run
  3. In the right panel, locate and delete the following entries:
    AVPSrv = "%Windows%\AVPSrv.exE"
    cmdbcs = "%Windows%\cmdbcs.exe"
    DbgHlp32 = "%Windows%\DbgHlp32.exe"
    Kvsc3 = "%Windows%\Kvsc3.exE"
    LotusHlp = "%Windows%\LotusHlp.exe"
    mppds = "%Windows%\mppds.exe"
    msccrt = "%Windows%\msccrt.exe"
    MsIMMs32 = "%Windows%\MsIMMs32.exE"
    MsPrint32D = "%Windows%\MsPrint32D.exe"
    NAVMon32 = "%Windows%\NAVMon32.exE"
    NVDispDrv = "%Windows%\NVDispDRV.EXE"
    PTSShell = "%Windows%\PTSShell.exe"
    RegSrv64D = "%Windows%\RegSrv64D.exE"
    SHAProc = "%Windows%\SHAProc.exe"
    upxdnd = "%Windows%\upxdnd.exe"
    WinForm = "%Windows%\WinForm.exE"
    WinSysM = "%Windows%\371662M.exe"
    WinSysW = "%Windows%\371662L.exe"
    WSockDrv32 = "%Windows%\WSockDrv32.exe"

    (Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
  4. In the left panel, double-click the following:
    HKEY_CURRENT_USER>SYSTEM>CurrentControlSet>Services
  5. Still in the left panel, locate and delete the key:
    2C7E4380

Removing Other Malware Entries from the Registry

  1. Still in Registry Editor, in the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows NT
  2. In the right panel, locate and delete the entry:
    ReportBootOk = "1"
  3. Close Registry Editor.

Deleting/Restoring Other Registry Entries

  1. Still in Registry Editor, in the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>PCHealth>ErrorReporting
  2. In the right panel, locate the entry:
    DoReport = "0"
  3. Right-click on the value name and choose Modify. Change the value data of this entry to:
    1
  4. In the right panel, locate the entry:
    ShowUI = "0"
  5. Right-click on the value name and choose Modify. Change the value data of this entry to:
    1
  6. In the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows>
    CurrentVersion>Explorer>Advanced>Folder>Hidden>SHOWALL
  7. In the right panel, locate the entry:
    CheckedValue = "0"
  8. Right-click on the value name and choose Modify. Change the value data of this entry to:
    1
  9. Close Registry Editor.

Restoring Deleted, Modified, or Overwritten Files

Files that have been deleted, modified, or overwritten by this malware can be restored from backup or using installers.

Deleting Malware-created AUTORUN.INF/s

  1. Right-click Start then click Search... or Find..., depending on the version of Windows you are running.
  2. In the Named input box, type:
    AUTORUN.INF
  3. In the Look In drop-down list, select a drive, then press Enter.
  4. Select the file, then open using Notepad.
  5. Check if the following lines are present in the file:
    [AutoRun]
    open=auto.exe
    shellexecute=auto.exe
    shell\Auto\command=auto.exe
  6. If the lines are present, delete the file.
  7. Repeat steps 3 to 6 for AUTORUN.INF files in the remaining removable drives.
  8. Close Search Results.

Running Trend Micro Antivirus

If you are currently running in safe mode, please restart your computer normally before performing the following solution.

Scan your computer with Trend Micro antivirus and delete files detected as WORM_WINKO.AO, TSPY_FRETHOG.KH, TSPY_FRETHOG.MU, TSPY_FRETHOG.NE, TSPY_FRETHOG.NU, TSPY_FRETHOG.OL, TSPY_LEGMIR.CSF, TSPY_LEGMIR.CTN, TSPY_LEGMIR.DAJ, TSPY_LEGMIR.FK, TSPY_LOLYDA.J, TSPY_ONLINEG.AXC, TSPY_ONLINEG.AXJ, TSPY_ONLINEG.BUI, TSPY_ONLINEG.BUJ, TSPY_ONLINEG.BUR, TSPY_ONLINEG.BUW, TSPY_ONLINEG.BVA, TSPY_ONLINEG.BVB, TSPY_ONLINEG.BVC, TSPY_ONLINEG.BVE, TSPY_ONLINEG.BVF, TSPY_ONLINEG.NSM, and TSPY_ONLINEG.OLS. To do this, Trend Micro customers must download the latest virus pattern file and scan their computers. Other Internet users can use HouseCall, the Trend Micro online threat scanner.




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