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Backdoor.Win32.Farfli_ba52d06b40


Trojan-Dropper.MSIL.Agent.aoiq (Kaspersky), Backdoor.Win32.Farfli.FD, Backdoor.Win32.Xtrat.FD, Trojan.Win32.IEDummy.FD, GenericAutorunWorm.YR, GenericInjector.YR (Lavasoft MAS)Behaviour: Trojan-Dropper, Trojan, Backdoor, Worm, WormAutorun

The description has been automatically generated by Lavasoft Malware Analysis System and it may contain incomplete or inaccurate information.

Summary

MD5: ba52d06b40f2e45f1522a75f5a1a2450

SHA1: 3d1f66c5b42fffc82c177257808257b6d9ac3b9c

SHA256: c77ff802a129edc3215b2378c14aa164545382b3f2700f5800274c7f7ccc7c2e

SSDeep: 3072:gQktcI/quqtEB9kIdj m8Sz449Rg/HJyn3dT:lkz2tHIdj PU44jg/HO

Size: 147640 bytes

File type: EXE

Platform: WIN32

Entropy: Packed

PEID: MicrosoftVisualC, NETexecutable, UPolyXv05_v6

Company: no certificate found

Created at: 2013-04-10 19:05:40

Analyzed on: WindowsXP SP3 32-bit

Summary: Backdoor. Malware that enables a remote control of victim's machine.

Dynamic Analysis

Payload

Behaviour Description
WormAutorunA worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Backdoor's file once a user opens a drive's folder in Windows Explorer.


Process activity

The Backdoor creates the following process(es):

AppLaunch.exe:1324
DW20.EXE:1596

The Backdoor injects its code into the following process(es):

vmnethcp.exe:672
%original file name%.exe:548
iexplore.exe:1700

File activity

The process %original file name%.exe:548 makes changes in the file system.


The Backdoor creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Templates\vmnethcp.exe (7 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\BioCredProv.exe (673 bytes)

The process AppLaunch.exe:1324 makes changes in the file system.


The Backdoor deletes the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temp\x.html (0 bytes)

The process iexplore.exe:1700 makes changes in the file system.


The Backdoor creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Application Data\Microsoft\Windows\YUKMTbZijxPe.dat (314 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%System%\aerytn\javaj.exe (59 bytes)

The process DW20.EXE:1596 makes changes in the file system.


The Backdoor creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temp\dw.log (78 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\BCD4D.dmp (295389 bytes)

Registry activity

The process vmnethcp.exe:672 makes changes in the system registry.


The Backdoor creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "A8 B1 28 5B A2 1B 80 D0 EE 61 92 94 49 4D E7 A8"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

The process %original file name%.exe:548 makes changes in the system registry.


The Backdoor creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "C8 26 FB A3 A6 D5 E0 73 11 01 7F 81 93 D6 85 94"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd73-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common Documents" = "%Documents and Settings%\All Users\Documents"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Desktop" = "%Documents and Settings%\%current user%\Desktop"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd72-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd75-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
"Templates" = "%Documents and Settings%\%current user%\Templates"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{b98117e8-75ca-11e2-81b2-000c293708fb}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\ShellNoRoam\MUICache\%Documents and Settings%\%current user%\Templates]
"vmnethcp.exe" = "System Monitor Control"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common Desktop" = "%Documents and Settings%\All Users\Desktop"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Personal" = "%Documents and Settings%\%current user%\My Documents"

The Backdoor modifies IE settings for security zones to map all local web-nodes with no dots which do not refer to any zone to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "1"

The Backdoor modifies IE settings for security zones to map all web-nodes that bypassing proxy to the Intranet Zone:

"ProxyBypass" = "1"

The Backdoor modifies IE settings for security zones to map all urls to the Intranet Zone:

"IntranetName" = "1"

The process AppLaunch.exe:1324 makes changes in the system registry.


The Backdoor creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "C8 6C 18 B6 A6 68 47 D3 49 E6 5D 00 15 A6 4A FB"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd73-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd72-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{b98117e8-75ca-11e2-81b2-000c293708fb}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd75-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\XtremeRAT]
"Mutex" = "YUKMTbZijxPe"

The process iexplore.exe:1700 makes changes in the system registry.


The Backdoor creates and/or sets the following values in system registry:

[HKCU\Software\YUKMTbZijxPe]
"ServerName" = "%System%\aerytn\javaj.exe"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Directory" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4]
"CacheLimit" = "65452"
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache4"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 17 00 00 00 01 00 00 00 00 00 00 00"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd73-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\{F8S8YCTU-0433-WM87-14R8-M1FKRF7AF5FB}]
"StubPath" = "%System%\aerytn\javaj.exe restart"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication]
"ID" = "1208111653"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache2"

[HKCU\Software\YUKMTbZijxPe]
"ServerStarted" = "25/01/2014 04:00:15"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd75-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication]
"Name" = "iexplore.exe"

[HKLM\System\CurrentControlSet\Hardware Profiles\0001\Software\Microsoft\windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CacheLimit" = "65452"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CacheLimit" = "65452"

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "1A E3 9F 4C C7 78 56 33 03 82 26 F7 DC 59 0B 10"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"MigrateProxy" = "1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd72-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{b98117e8-75ca-11e2-81b2-000c293708fb}]
"BaseClass" = "Drive"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache3"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Paths" = "4"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"History" = "%Documents and Settings%\%current user%\Local Settings\History"

The Backdoor modifies IE settings for security zones to map all local web-nodes with no dots which do not refer to any zone to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "1"

To automatically run itself each time Windows is booted, the Backdoor adds the following link to its file to the system registry autorun key:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"HKLM" = "%System%\aerytn\javaj.exe"

The Backdoor modifies IE settings for security zones to map all urls to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName" = "1"

The Backdoor modifies IE settings for security zones to map all web-nodes that bypassing proxy to the Intranet Zone:

"ProxyBypass" = "1"

To automatically run itself each time Windows is booted, the Backdoor adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"HKCU" = "%System%\aerytn\javaj.exe"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

The Backdoor deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"

The process DW20.EXE:1596 makes changes in the system registry.


The Backdoor creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "BE 12 19 91 62 6E D4 BF FA E1 C9 71 99 C6 B1 6D"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\System\CurrentControlSet\Hardware Profiles\0001\Software\Microsoft\windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache2"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"MigrateProxy" = "1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"History" = "%Documents and Settings%\%current user%\Local Settings\History"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Directory" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4]
"CacheLimit" = "65452"
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache4"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache3"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Paths" = "4"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 18 00 00 00 01 00 00 00 00 00 00 00"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Personal" = "%Documents and Settings%\%current user%\My Documents"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

The Backdoor deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"

Network activity (URLs)

No activity has been detected.

HOSTS file anomalies

No changes have been detected.

Rootkit activity

No anomalies have been detected.

Propagation

A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Backdoor's file once a user opens a drive's folder in Windows Explorer.

Removals

Remove it with Ad-Aware

  1. Click (here) to download and install Ad-Aware Free Antivirus.
  2. Update the definition files.
  3. Run a full scan of your computer.

Manual removal*

  1. Terminate malicious process(es) (How to End a Process With the Task Manager):

    AppLaunch.exe:1324
    DW20.EXE:1596

  2. Delete the original Backdoor file.
  3. Delete or disinfect the following files created/modified by the Backdoor:

    %Documents and Settings%\%current user%\Templates\vmnethcp.exe (7 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\BioCredProv.exe (673 bytes)
    %Documents and Settings%\%current user%\Application Data\Microsoft\Windows\YUKMTbZijxPe.dat (314 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
    %System%\aerytn\javaj.exe (59 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\dw.log (78 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\BCD4D.dmp (295389 bytes)

  4. Delete the following value(s) in the autorun key (How to Work with System Registry):

    [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
    "HKLM" = "%System%\aerytn\javaj.exe"

    [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
    "HKCU" = "%System%\aerytn\javaj.exe"

  5. Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
  6. Reboot the computer.
*Manual removal may cause unexpected system behaviour and should be performed at your own risk.

Static Analysis

Network Activity

Map

Strings from Dumps