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Virus:TR/Meredrop.A.12421
Date discovered:08/08/2010
Type:Trojan
In the wild:Yes
Reported Infections:Low to medium
Distribution Potential:Low to medium
Damage Potential:Low to medium
Static file:Yes
File size:189.440 Bytes
MD5 checksum:ada7ddfbc9abd5686fd8caa8a85b67d1
VDF version:7.10.09.170
IVDF version:7.10.10.104 - Sunday, August 8, 2010

 General Method of propagation:
   • Local network


Aliases:
   •  Mcafee: Downloader-CEW.a
   •  Kaspersky: Worm.Win32.Pinit.rl
   •  TrendMicro: TROJ_FAKEAV.SMZU
   •  Sophos: Mal/FakeAV-EI
     Avast: Win32:MalOb-BU
     Microsoft: Trojan:Win32/Meredrop
   •  Panda: W32/Pinit.M.worm
     PCTools: Trojan.FakeAV
   •  VirusBuster: Worm.Pinit.VN
AhnLab: Trojan/Win32.FakeAV
     Authentium: W32/Trojan2.NCZZ
     Fortinet: W32/Pinit.EI!worm
     Ikarus: Worm.Win32.Pinit
     Norman: W32/Pinit.CD


Platforms / OS:
   • Windows 2000
   • Windows XP
   • Windows 2003
    Windows Vista


Side effects:
   • Downloads files
   • Drops malicious files
   • Registry modification

 Files It copies itself to the following location:
   • %SYSDIR%\cooper.mine



The following files are created:

%SYSDIR%\user32.dll
%SYSDIR%\dllcache\user32.dll Detected as: TR/Patched.gq.16

%SYSDIR%\nmklo.dll Detected as: WORM/Pinit.MT

%SYSDIR%\h7t.wt
%SYSDIR%\ff4h.gy
%SYSDIR%\hgtd.ruy



It tries to download some files:

The location is the following:
   • silajopa.com/tpsa/gate/**********


The location is the following:
   • silajopa.com/tpsa/gate/**********




It tries to execute the following file:

Filename:
   • %SYSDIR%\Wbem\wmic.exe
using the following command line arguments: path win32_terminalservicesetting where (__Class!="") call setallowtsconnections 1

 Registry The following registry keys are added:

[HKLM\Software\microsoft\Windows NT\CURRENTVERSION\WINDOWS]
   • "Appiaat_Dlls"="nmklo"

[HKLM\SOFTWARE\1]
   • "31AC70412E939D72A9234CDEBB1AF5867B"="efipdhioiijnjpjcjmidigiggmgfgkgkhkhfcojedpemjgfcinfdff" "31897356954C2CD3D41B221E3F24F99BBA"=dword:03f940aa
   • "31C2E1E4D78E6A11B88DFA803456A1FFA5"=dword:00000000

[HKLM\SOFTWARE\3]
   • "31AC70412E939D72A9234CDEBB1AF5867B"="nqrckqqlqdrqrirprhqoqrqdopoinfnhmjmqrjrjlmmdmqrpmeqhmnng"
   • "31897356954C2CD3D41B221E3F24F99BBA"=dword:03f940aa
   • "31C2E1E4D78E6A11B88DFA803456A1FFA5"=dword:00000000

[HKLM\SOFTWARE\9]
   • "31AC70412E939D72A9234CDEBB1AF5867B"="kgomncpjpnogoconproiodorqjqoqhqfrprgmlmlocrhrlqnogkrpcpipp"
   • "31897356954C2CD3D41B221E3F24F99BBA"=dword:03f940aa
   • "31C2E1E4D78E6A11B88DFA803456A1FFA5"=dword:00000000

[HKLM\SYSTEM\ControlSet001\Control\Terminal Server\Licensing Core]
   • "EnableConcurrentSessions"=dword:00000001



The following registry key is changed:

[HKLM\SYSTEM\ControlSet001\Control\Terminal Server]
   New value:
   • "fDenyTSConnections"=dword:00000000

 Network Infection Exploit:
It makes use of the following Exploit:
– MS04-011 (LSASS Vulnerability)

 Process termination List of processes that are terminated:
   • zlclient.exe
   • outpost.exe
   • avgcc.exe
   • kpf4ss.exe
   • kavpf.exe
   • mpfsrv.exe


 Backdoor The following port is opened:

svchost.exe on TCP port 3389 in order to provide backdoor capabilities.

 File details Programming language:
The malware program was written in MS Visual C++.


Runtime packer:
In order to aggravate detection and reduce size of the file it is packed with a runtime packer.

Description inserted by Alexandru Dinu on Thursday, September 30, 2010
Description updated by Alexandru Dinu on Thursday, September 30, 2010

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