TROJ_COSSTA.SZV

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It deletes itself after execution.

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan creates the following folders:

• %System Root%\config
• %System Root%\config\ref
• %User Temp%\temp_log
• %User Temp%\temp_log\chat
• %User Temp%\temp_log\tmp
• %User Temp%\plugins
• %User Temp%\pls
• %User Temp%\goo
• %User Temp%\sss3cc5ec883ec
• %User Profile%\pzr6202a8682bc0
• %User Temp%\pzr6202a8682bc0
• %User Profile%\pzr6202a8682bc0\config
• %User Profile%\config\ref
• %User Temp%\pzr6202a8682bc0\temp_log
• %User Temp%\pzr6202a8682bc0\temp_log\chat
• %User Temp%\pzr6202a8682bc0\temp_log\tmp
• %User Temp%\pzr6202a8682bc0\plugins
• %User Temp%\pzr6202a8682bc0\pls
• %User Temp%\pzr6202a8682bc0\goo

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Other System Modifications

This Trojan deletes the following files:

• %System Root%\strings.txt
• %System Root%\AUTOEXEC.BAT
• %System Root%\config\tm.t
• %System Root%\config\script.txt
• %System Root%\config\update.txt
• %System Root%\config\configure
• %System Root%\config\notor
• %System Root%\config\name.drv
• %System Root%\config\exitd.vxd
• %System Root%\CONFIG.SYS
• %User Temp%\58e0ef.mst
• %User Temp%\AdobeARM.log
• %User Temp%\AdobeSFX.log
• %User Temp%\ASPNETSetup_00000.log
• %User Temp%\ASPNETSetup_00001.log
• %User Temp%\ASPNETSetup_00002.log
• %User Temp%\dd_depcheck_NETFX_EXP_35.txt
• %User Temp%\dd_dotnetfx35error.txt
• %User Temp%\dd_dotnetfx35install.txt
• %User Temp%\dd_dotNetFx40_Full_x86_x64_decompression_log.txt
• %User Temp%\dd_MSXML6_MSI0686.txt
• %User Temp%\dd_netfx20MSI7F16.txt
• %User Temp%\dd_netfx20UI7F16.txt
• %User Temp%\dd_NET_Framework20_Setup06A7.txt
• %User Temp%\dd_NET_Framework30_Setup0775.txt
• %User Temp%\dd_NET_Framework35_MSI07B9.txt
• %User Temp%\dd_RGB9RAST_x86.msi0683.txt
• %User Temp%\dd_vcredistMSI3CAA.txt
• %User Temp%\dd_vcredistMSI7C21.txt
• %User Temp%\dd_vcredistUI3CAA.txt
• %User Temp%\dd_vcredistUI7C21.txt
• %User Temp%\dd_wcf_CA_smci_20111017_044900_062.txt
• %User Temp%\dd_wcf_retCA29BA.txt
• %User Temp%\dd_WIC.txt
• %User Temp%\dd_XPS.txt
• %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Core_x86.msi.txt
• %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Extended_x86.msi.txt
• %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578.html
• %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642-MSI_vc_red.msi.txt
• %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642.html
• %User Temp%\tproc.1
• %User Temp%\tproc.2
• %User Temp%\usb.exit
• %User Temp%\uxeventlog.txt
• %User Temp%\vminst.log_20111016_212239_Failed.log
• %User Temp%\vminst.log_20130313_012028.log
• %User Temp%\vminst.log_20130313_012352_Failed.log
• %User Temp%\vmmsi.log_20111016_212246_Failed.log
• %User Temp%\vmmsi.log_20130313_012028.log
• %User Temp%\vmmsi.log_20130313_012352_Failed.log
• %User Temp%\WSFF8.tmp
• %User Temp%\WSFF9.tmp

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

It deletes the following folders:

• %User Temp%\Microsoft .NET Framework 4 Setup_4.0.30319
• %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_10.0.30319
• %User Temp%\{835818DD-220C-4ABD-946E-0D8660B95E29}

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Dropping Routine

This Trojan drops the following files:

• %User Startup%\{malware file name}.lnk
• %User Profile%\config\notor
• %User Profile%\config\script.txt
• %User Profile%\config\update.txt
• %User Profile%\config\configure
• %User Profile%\config\name.drv
• %User Profile%\config\exitd.vxd

(Note: %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Other Details

This Trojan connects to the following possibly malicious URL:

• http://dasan.{BLOCKED}g.ac.kr/~appmath/test/bbs/strings.txt
• http://www.{BLOCKED}e.com.br
• http://www.{BLOCKED}o.com
• http://www.{BLOCKED}n.com
• http://www.{BLOCKED}a.com.br
• http://www.{BLOCKED}ess.com
• http://www.{BLOCKED}hanin.org/bbs/include/eu.txt
• http://www.{BLOCKED}ysolutions.com/.../IRPF2008/rwk.txt
• http://www.{BLOCKED}lm.com.ua/forum/files/.../rwk.txt
• {BLOCKED}7.239.150
• {BLOCKED}0.1
• {BLOCKED}.228.23
• {BLOCKED}.180.149
• {BLOCKED}2.82.163
• {BLOCKED}169.244
• {BLOCKED}.123.234
• {BLOCKED}.250.153
• {BLOCKED}.4.62

It deletes itself after execution.

This report is generated via an automated analysis system.