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Backdoor.Win32.PcClient_2c42a17c81


Trojan.Crypt.IW (BitDefender), TrojanDownloader:Win32/Dogkild.O (Microsoft), Trojan-Dropper.Win32.Mudrop.aod (Kaspersky), Trojan.Win32.Agent.a (fs) (VIPRE), Trojan.MulDrop.32002 (DrWeb), Trojan.Crypt.IW (B) (Emsisoft), Generic Dropper.jz (McAfee), Suspicious.MH690.A (Symantec), Trojan-Dropper.Win32.Mudrop (Ikarus), Worm/AutoRun.IZ (AVG), Win32:Agent-AFRT [Rtk] (Avast), TROJ_GERAL.SMQ (TrendMicro), Backdoor.Win32.PcClient.FD, GenericAutorunWorm.YR (Lavasoft MAS)Behaviour: Trojan-Dropper, Trojan-Downloader, 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: 2c42a17c818004580a1ed11003ea639e

SHA1: ccc3e25550fc1c7b144c47b747e9b9fd1e8e5fac

SHA256: 2023a0c370c51981239386a5be99612302e2df9f89e832dab5ade446c4615d15

SSDeep: 12288:xOEFz4KDelgGGnVAAtZMC12BXnh6ya sNzaOvoJpaz/g/J/vVQT:7VKlX8VAAtZp43u sNH8az/g/J/NQ

Size: 1106757 bytes

File type: EXE

Platform: WIN32

Entropy: Not Packed

PEID: UPolyXv05_v6

Company: no certificate found

Created at: 2009-06-12 08:27:02

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):

taskkill.exe:3116
taskkill.exe:3764
taskkill.exe:3616
sc.exe:136
rundll32.exe:1172

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

%original file name%.exe:4044

File activity

The process rundll32.exe:1172 makes changes in the file system.


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

%System%\drivers\acpiec.sys (12672 bytes)

The process %original file name%.exe:4044 makes changes in the file system.


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

%WinDir%\Driver Cache\i386 (4096 bytes)
%System%\wbem\Repository\FS\OBJECTS.MAP (12288 bytes)
D:\1.exe (1106757 bytes)
%WinDir%\repair (4096 bytes)
%System%\func.dll (36353 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp (4096 bytes)
C:\autorun.inf (21 bytes)
%System%\CatRoot2\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} (4096 bytes)
%WinDir%\LastGood\system32 (4096 bytes)
%System%\drivers\etc\hosts (5743 bytes)
%WinDir% (4096 bytes)
%System%\drivers\pcidump.sys (11905 bytes)
%System%\dllcache (4096 bytes)
%WinDir%\inf (8192 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%System%\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} (4096 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\test.pml (9359360 bytes)
%System%\config (4096 bytes)
%System%\drivers (4096 bytes)
%WinDir%\phpi.dll (45569 bytes)
D:\autorun.inf (21 bytes)
%System%\wbem\Repository\FS\MAPPING1.MAP (28672 bytes)
C:\1.exe (1106757 bytes)

Registry activity

The process taskkill.exe:3116 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 05 0F BD FD A9 AC F5 1C F4 0F D9 A2 A8 00 A5"

The process taskkill.exe:3764 makes changes in the system registry.


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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "16 26 54 97 64 50 A2 EA 94 5B 14 9C F9 F7 63 BF"

The process taskkill.exe:3616 makes changes in the system registry.


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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "E7 52 73 4F B0 B2 0F 15 56 86 8D 24 7C 6B 93 C9"

The process sc.exe:136 makes changes in the system registry.


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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "65 CB 54 AE 06 0E 01 D4 43 E3 7E 58 35 0B 12 7F"

The process rundll32.exe:1172 makes changes in the system registry.


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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "87 A8 7D 50 4A 86 63 3F BB DB 1B 04 52 F5 D9 52"

Network activity (URLs)

URL IP
2a8k.cnUnresolvable


HOSTS file anomalies

The Backdoor modifies "%System%\drivers\etc\hosts" file which is used to translate DNS entries to IP addresses. The modified file is 5743 bytes in size. The following strings are added to the hosts file listed below:

127.0.0.1v.onondown.com.cn
127.0.0.2ymsdasdw1.cn
127.0.0.3h96b.info
127.0.0.0fuck.zttwp.cn
127.0.0.0www.hackerbf.cn
127.0.0.0geekbyfeng.cn
127.0.0.0121.14.101.68
127.0.0.0ppp.etimes888.com
127.0.0.0www.bypk.com
127.0.0.0CSC3-2004-crl.verisign.com
127.0.0.1va9sdhun23.cn
127.0.0.0udp.hjob123.com
127.0.0.2bnasnd83nd.cn
127.0.0.0www.gamehacker.com.cn
127.0.0.0gamehacker.com.cn
127.0.0.3adlaji.cn
127.0.0.1858656.com
127.1.1.1bnasnd83nd.cn
127.0.0.1my123.com
127.0.0.0user1.12-27.net
127.0.0.18749.com
127.0.0.0fengent.cn
127.0.0.14199.com
127.0.0.1user1.16-22.net
127.0.0.17379.com
127.0.0.12be37c5f.3f6e2cc5f0b.com
127.0.0.17255.com
127.0.0.1user1.23-12.net
127.0.0.13448.com
127.0.0.1www.guccia.net
127.0.0.17939.com
127.0.0.1a.o1o1o1.nEt
127.0.0.18009.com
127.0.0.1user1.12-73.cn
127.0.0.1piaoxue.com
127.0.0.13n8nlasd.cn
127.0.0.1kzdh.com
127.0.0.0www.sony888.cn
127.0.0.1about.blank.la
127.0.0.0user1.asp-33.cn
127.0.0.16781.com
127.0.0.0www.netkwek.cn
127.0.0.17322.com
127.0.0.0ymsdkad6.cn
127.0.0.0www.lkwueir.cn
127.0.0.106.jacai.com
127.0.1.1user1.23-17.net
127.0.0.11.jopenkk.com
127.0.0.0upa.luzhiai.net
127.0.0.11.jopenqc.com
127.0.0.0www.guccia.net
127.0.0.11.joppnqq.com
127.0.0.04m9mnlmi.cn
127.0.0.11.xqhgm.com
127.0.0.0mm119mkssd.cn
127.0.0.1100.332233.com
127.0.0.061.128.171.115:8080
127.0.0.1121.11.90.79
127.0.0.0www.1119111.com
127.0.0.1121565.net
127.0.0.0win.nihao69.cn
127.0.0.1125.90.88.38
127.0.0.116888.6to23.com
127.0.0.12.joppnqq.com
127.0.0.0puc.lianxiac.net
127.0.0.1204.177.92.68
127.0.0.0pud.lianxiac.net
127.0.0.1210.74.145.236
127.0.0.0210.76.0.133
127.0.0.1219.129.239.220
127.0.0.061.166.32.2
127.0.0.1219.153.40.221
127.0.0.0218.92.186.27
127.0.0.1219.153.46.27
127.0.0.0www.fsfsfag.cn
127.0.0.1219.153.52.123
127.0.0.0ovo.ovovov.cn
127.0.0.1221.195.42.71
127.0.0.0dw.com.com
127.0.0.1222.73.218.115
127.0.0.1203.110.168.233:80
127.0.0.13.joppnqq.com
127.0.0.1203.110.168.221:80
127.0.0.1363xx.com
127.0.0.1www1.ip10086.com.cm
127.0.0.14199.com
127.0.0.1blog.ip10086.com.cn
127.0.0.143242.com
127.0.0.1www.ccji68.cn
127.0.0.15.xqhgm.com
127.0.0.0t.myblank.cn
127.0.0.1520.mm5208.com
127.0.0.0x.myblank.cn
127.0.0.159.34.131.54
127.0.0.1210.51.45.5
127.0.0.159.34.198.228
127.0.0.1www.ew1q.cn
127.0.0.159.34.198.88
127.0.0.159.34.198.97
127.0.0.160.190.114.101
127.0.0.160.190.218.34
127.0.0.0qq-xing.com.cn
127.0.0.160.191.124.252
127.0.0.161.145.117.212
127.0.0.161.157.109.222
127.0.0.175.126.3.216
127.0.0.175.126.3.217
127.0.0.175.126.3.218
127.0.0.059.125.231.177:17777
127.0.0.175.126.3.220
127.0.0.175.126.3.221
127.0.0.175.126.3.222
127.0.0.1772630.com
127.0.0.1832823.cn
127.0.0.18749.com
127.0.0.1888.jopenqc.com
127.0.0.189382.cn
127.0.0.18v8.biz
127.0.0.197725.com
127.0.0.19gg.biz
127.0.0.1www.9000music.com
127.0.0.1test.591jx.com
127.0.0.1a.topxxxx.cn
127.0.0.1picon.chinaren.com
127.0.0.1www.5566.net
127.0.0.1p.qqkx.com
127.0.0.1news.netandtv.com
127.0.0.1z.neter888.cn
127.0.0.1b.myblank.cn
127.0.0.1wvw.wokutu.com
127.0.0.1unionch.qyule.com
127.0.0.1www.qyule.com
127.0.0.1it.itjc.cn
127.0.0.1www.linkwww.com
127.0.0.1vod.kaicn.com
127.0.0.1www.tx8688.com
127.0.0.1b.neter888.cn
127.0.0.1promote.huanqiu.com
127.0.0.1www.huanqiu.com
127.0.0.1www.haokanla.com
127.0.0.1play.unionsky.cn
127.0.0.1www.52v.com
127.0.0.1www.gghka.cn
127.0.0.1icon.ajiang.net
127.0.0.1new.ete.cn
127.0.0.1www.stiae.cn
127.0.0.1o.neter888.cn
127.0.0.1comm.jinti.com
127.0.0.1www.google-analytics.com
127.0.0.1hz.mmstat.com
127.0.0.1www.game175.cn
127.0.0.1x.neter888.cn
127.0.0.1z.neter888.cn
127.0.0.1p.etimes888.com
127.0.0.1hx.etimes888.com
127.0.0.1abc.qqkx.com
127.0.0.1dm.popdm.cn
127.0.0.1www.yl9999.com
127.0.0.1www.dajiadoushe.cn
127.0.0.1v.onondown.com.cn
127.0.0.1www.interoo.net
127.0.0.1bally1.bally-bally.net
127.0.0.1www.bao5605509.cn
127.0.0.1www.rty456.cn
127.0.0.1www.werqwer.cn
127.0.0.11.360-1.cn
127.0.0.1user1.23-16.net
127.0.0.1www.guccia.net
127.0.0.1www.interoo.net
127.0.0.1upa.netsool.net
127.0.0.1js.users.51.la
127.0.0.1vip2.51.la
127.0.0.1web.51.la
127.0.0.1qq.gong2008.com
127.0.0.12008tl.copyip.com
127.0.0.1tla.laozihuolaile.cn
127.0.0.1www.tx6868.cn
127.0.0.1p001.tiloaiai.com
127.0.0.1s1.tl8tl.com
127.0.0.1s1.gong2008.com
127.0.0.14b3ce56f9g.3f6e2cc5f0b.com


Rootkit activity

The Backdoor installs the following kernel-mode hooks:

ZwQuerySystemInformation

The Backdoor substitutes IRP handlers in a file system driver (FastFAT) to control operations with files:

MJ_CREATE

The Backdoor substitutes IRP handlers in a file system driver (NTFS) to control operations with files:

MJ_CREATE

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. Scan a system with an anti-rootkit tool.
  2. Terminate malicious process(es) (How to End a Process With the Task Manager):

    taskkill.exe:3116
    taskkill.exe:3764
    taskkill.exe:3616
    sc.exe:136
    rundll32.exe:1172

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

    %System%\drivers\acpiec.sys (12672 bytes)
    %WinDir%\Driver Cache\i386 (4096 bytes)
    %System%\wbem\Repository\FS\OBJECTS.MAP (12288 bytes)
    D:\1.exe (1106757 bytes)
    %WinDir%\repair (4096 bytes)
    %System%\func.dll (36353 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp (4096 bytes)
    C:\autorun.inf (21 bytes)
    %System%\CatRoot2\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} (4096 bytes)
    %WinDir%\LastGood\system32 (4096 bytes)
    %System%\drivers\etc\hosts (5743 bytes)
    %System%\drivers\pcidump.sys (11905 bytes)
    %System%\dllcache (4096 bytes)
    %WinDir%\inf (8192 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
    %System%\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} (4096 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\test.pml (9359360 bytes)
    %System%\config (4096 bytes)
    %WinDir%\phpi.dll (45569 bytes)
    D:\autorun.inf (21 bytes)
    %System%\wbem\Repository\FS\MAPPING1.MAP (28672 bytes)
    C:\1.exe (1106757 bytes)

  5. Restore the original content of the HOSTS file (%System%\drivers\etc\hosts): 127.0.0.1 localhost
  6. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
  7. Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
  8. 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