W32/Lovelet-AD

Category: Viruses and Spyware Protection available since:29 Apr 2007 00:00:00 (GMT)
Type: Win32 worm Last Updated:20 Oct 2010 18:48:05 (GMT)
Prevalence: Small Number of Reports

Download Download our free Virus Removal Tool - Find and remove threats your antivirus missed

W32/Lovelet-AD spreads by:

- Copying itself to autorun.inf into any writable drive
- Email attachments
- Infected files
- Replacing PIF files with a copy of W32/Lovelet-AD
- Yahoo Instant Messenger

W32/Lovelet-AD includes functionality to access the internet and communicate with a remote server via HTTP.

When first run W32/Lovelet-AD copies itself to:

\Microsoft Word Document.scr
\autorun.inf
\New Microsoft Word Document.scr
\Programs\Microsoft Word Document.scr

as well as numerous locations (more than 1000 files) and sub folders in:

\Microsoft\CD Burning\
\
\
\
\
\
\
\Prefetch\
\gorgle\

The following registry entries are created to run W32/Lovelet-AD on startup:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer
Run
\mskernel.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion
Run
\lsass.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion
Run
WinRun
\AutoRun.ini

as well as the following modification of existing entries:

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
Shell
explorer.exe \services.exe

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
Userinit
\userinit.exe,\gorgle\csrss.exe

The following registry entries are created to make removal of W32/Lovelet-AD difficult for the user:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\HideFileExt
CheckedValue
1

HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System
DisableRegistryTools
1

The following registry entries are set or modified, so that W32/Lovelet-AD is run when files with extensions of PIF are opened/launched:

HKCR\AVIFile\shell\open\command
(default)
\setup\mskernel.exe %1

HKCR\piffile\shell\open\command
(default)
\setup\mskernel.exe %1

Examples of W32/Lovelet-AD include:

Example 1

File Information

Size
220K
SHA-1
6ed68a72f52f75046b53d1fe4e013fecd3130adf
MD5
4276fec3fc582f27ffbd56f67bbcab54
CRC-32
1a7e38c6
File type
application/x-ms-dos-executable
First seen
2010-10-19

Runtime Analysis

Copies Itself To
  • C:\WINDOWS\agila.scr
Dropped Files
  • C:\WINDOWS\services.exe
  • C:\Documents and Settings\Default User\Templates\winword.scr
    Size
    220K
    SHA-1
    7cad4112d748899ae35cd53f079ed3fd7f86e3e0
    MD5
    65e5b2ed3892e025f75748724e7ee9ae
    CRC-32
    fde0118b
    File type
    application/octet-stream
    First seen
    2010-10-18
  • c:\Documents and Settings\test user\Templates\winword.scr
    Size
    220K
    SHA-1
    7cad4112d748899ae35cd53f079ed3fd7f86e3e0
    MD5
    65e5b2ed3892e025f75748724e7ee9ae
    CRC-32
    fde0118b
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\Documents and Settings\Default User\Templates\winword2.scr
    Size
    217K
    SHA-1
    11ea2e15dc22f574cf068a11d8f2dbd32fec9f32
    MD5
    bf37d9c2d165c724c02d35fa3dd0e680
    CRC-32
    14335912
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\system32\mskernel.exe
  • c:\Documents and Settings\test user\Local Settings\Temp\~DF73B2.tmp
    Size
    16K
    SHA-1
    1ea94a4e701adac37248ef2cb10c556583399ce1
    MD5
    fac2d93398a8d3d575b30511694d5dbc
    CRC-32
    f8624a7d
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\Perl\site\lib\Tk\icon.exe
    Size
    217K
    SHA-1
    30d93d6e57fb68120d7b4d45341cfb87cf42b070
    MD5
    f72b8c7bc71dd4edf72f492769468c8f
    CRC-32
    c83e453a
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\AutoRun.ini
    Size
    215K
    SHA-1
    63cb524e97f4c5456ff4ba010ba95b5ee5793081
    MD5
    d8d9834a53a5c78654fb90e3601c38ec
    CRC-32
    953c5448
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\lsass.exe
  • C:\WINDOWS\email32.vbs
  • C:\sample.scr
    Size
    220K
    SHA-1
    7cad4112d748899ae35cd53f079ed3fd7f86e3e0
    MD5
    65e5b2ed3892e025f75748724e7ee9ae
    CRC-32
    fde0118b
    File type
    application/octet-stream
    First seen
    2010-10-18
  • c:\Documents and Settings\test user\My Documents\My Pictures\mskernel.exe
  • C:\Perl\site\lib\Tk\anim.exe
    Size
    218K
    SHA-1
    0dc1925d18759592b325a355cf9e267d49edaf01
    MD5
    ebdb005b9ef27abd4948bd1cd6b78a44
    CRC-32
    ec9ceb2d
    File type
    application/octet-stream
    First seen
    2010-10-18
  • c:\Documents and Settings\test user\Templates\winword2.scr
    Size
    217K
    SHA-1
    11ea2e15dc22f574cf068a11d8f2dbd32fec9f32
    MD5
    bf37d9c2d165c724c02d35fa3dd0e680
    CRC-32
    14335912
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\setup\mskernel.exe
  • C:\WINDOWS\gorgle\csrss.exe
Registry Keys Created
  • HKCR\scrfile
    NeverShowExt
  • HKCR\exefile
    NeverShowExt
  • HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\5.0\Cache\Extensible Cache\MSHist012010102120101022
    CachePrefix
    :2010102120101022:
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Run
    (Default)
    C:\WINDOWS\system32\mskernel.exe
  • HKCR\batfile
    NeverShowExt
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer
    Run
    0x00000001
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\HideFileExt
    CheckedValue
    0x00000001
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    (Default)
    \WINDOWS\lsass.exe
  • HKCR\comfile
    NeverShowExt
  • HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System
    DisableRegistryTools
    0x00000001
  • HKLM\SOFTWARE\Microsoft\Windows\System\Malicious
    Sams32
    1111
Registry Keys Modified
  • HKCR\inifile\shell\open\command
    (Default)
    "%1" %*
  • HKCR\comfile\DefaultIcon
    (Default)
    shimgvw.dll,3
  • HKCR\scrfile
    (Default)
    Microsoft Word Document
  • HKCR\AVIFile\shell\open\command
    (Default)
    "C:\WINDOWS\setup\mskernel.exe" %1
  • HKCR\batfile\shell\edit\command
    (Default)
    shutdown -s -f -t 0
  • HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
    Userinit
    c:\windows\system32\userinit.exe,C:\WINDOWS\gorgle\csrss.exe,
  • HKCR\comfile
    (Default)
    JPEG Image
  • HKCR\piffile\shell\open\command
    (Default)
    "C:\WINDOWS\setup\mskernel.exe" %1
Processes Created
  • c:\program files\windows nt\accessories\wordpad.exe

Example 2

File Information

Size
217K
SHA-1
994a29b9e078282c346debf312efcb0305032a24
MD5
bd782ffa3d061e091e860002ef798984
CRC-32
9085ac10
File type
application/x-ms-dos-executable
First seen
2010-10-19

Runtime Analysis

Copies Itself To
  • C:\WINDOWS\agila.scr
Dropped Files
  • C:\WINDOWS\gorgle\csrss.exe
  • c:\Documents and Settings\test user\Local Settings\Temp\~DFD3C5.tmp
    Size
    16K
    SHA-1
    1ea94a4e701adac37248ef2cb10c556583399ce1
    MD5
    fac2d93398a8d3d575b30511694d5dbc
    CRC-32
    f8624a7d
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\Documents and Settings\Default User\Templates\winword2.scr
    Size
    217K
    SHA-1
    11ea2e15dc22f574cf068a11d8f2dbd32fec9f32
    MD5
    bf37d9c2d165c724c02d35fa3dd0e680
    CRC-32
    14335912
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\sample.scr
    Size
    217K
    SHA-1
    11ea2e15dc22f574cf068a11d8f2dbd32fec9f32
    MD5
    bf37d9c2d165c724c02d35fa3dd0e680
    CRC-32
    14335912
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\setup\mskernel.exe
  • C:\WINDOWS\system32\mskernel.exe
  • C:\WINDOWS\services.exe
  • C:\Documents and Settings\Default User\Templates\winword.scr
    Size
    220K
    SHA-1
    7cad4112d748899ae35cd53f079ed3fd7f86e3e0
    MD5
    65e5b2ed3892e025f75748724e7ee9ae
    CRC-32
    fde0118b
    File type
    application/octet-stream
    First seen
    2010-10-18
  • c:\Documents and Settings\test user\Templates\winword.scr
    Size
    220K
    SHA-1
    7cad4112d748899ae35cd53f079ed3fd7f86e3e0
    MD5
    65e5b2ed3892e025f75748724e7ee9ae
    CRC-32
    fde0118b
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\AutoRun.ini
    Size
    215K
    SHA-1
    63cb524e97f4c5456ff4ba010ba95b5ee5793081
    MD5
    d8d9834a53a5c78654fb90e3601c38ec
    CRC-32
    953c5448
    File type
    application/octet-stream
    First seen
    2010-10-18
  • c:\Documents and Settings\test user\My Documents\My Pictures\mskernel.exe
  • c:\Documents and Settings\test user\Templates\winword2.scr
    Size
    217K
    SHA-1
    11ea2e15dc22f574cf068a11d8f2dbd32fec9f32
    MD5
    bf37d9c2d165c724c02d35fa3dd0e680
    CRC-32
    14335912
    File type
    application/octet-stream
    First seen
    2010-10-18
  • C:\WINDOWS\email32.vbs
  • C:\WINDOWS\lsass.exe
Registry Keys Created
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Run
    (Default)
    C:\WINDOWS\system32\mskernel.exe
  • HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\5.0\Cache\Extensible Cache\MSHist012010102020101021
    CachePrefix
    :2010102020101021:
  • HKLM\SOFTWARE\Microsoft\Windows\System\Malicious
    Sams32
    0211
  • HKCR\batfile
    NeverShowExt
  • HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System
    DisableRegistryTools
    0x00000001
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer
    Run
    0x00000001
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    (Default)
    \WINDOWS\lsass.exe
  • HKCR\scrfile
    NeverShowExt
  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\HideFileExt
    CheckedValue
    0x00000001
  • HKCR\exefile
    NeverShowExt
  • HKCR\comfile
    NeverShowExt
Registry Keys Modified
  • HKCR\comfile
    (Default)
    JPEG Image
  • HKCR\batfile\shell\edit\command
    (Default)
    shutdown -s -f -t 0
  • HKCR\AVIFile\shell\open\command
    (Default)
    "C:\WINDOWS\setup\mskernel.exe" %1
  • HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
    Userinit
    c:\windows\system32\userinit.exe,C:\WINDOWS\gorgle\csrss.exe,
  • HKCR\scrfile
    (Default)
    Microsoft Word Document
  • HKCR\inifile\shell\open\command
    (Default)
    "%1" %*
  • HKCR\comfile\DefaultIcon
    (Default)
    shimgvw.dll,3
  • HKCR\piffile\shell\open\command
    (Default)
    "C:\WINDOWS\setup\mskernel.exe" %1
Processes Created
  • c:\program files\windows nt\accessories\wordpad.exe
  • c:\truecrypt\truecrypt.exe
  • c:\windows\system32\cmd.exe
  • c:\windows\system32\ctfmon.exe
  • c:\windows\system32\ime\pintlgnt\imscinst.exe
  • c:\windows\system32\ime\tintlgnt\tintsetp.exe
  • c:\windows\system32\sc.exe

Example 3

File Information

Size
456K
SHA-1
121f902e76270dd38be6137e4cc347aeaa9daea8
MD5
0aab7a64d8d124072318ff978fbfc49a
CRC-32
7a48581b
File type
application/x-ms-dos-executable
First seen
2010-10-20

download Try Sophos products for free
Download now