ALIASES:

TrojanDownloader:Win32/Bancos.FP (Microsoft); Qhost-Gen!l (McAfee); Trojan.Gen (Symantec); Trojan-Downloader.Win32.VB.apxk, Trojan-Downloader.Win32.VB.apxk (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Backdoor.VB.Agent.BR (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Spyware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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

It modifies files, disabling programs and applications from properly running.

  TECHNICAL DETAILS

File Size: 77,872 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 02 May 2012

Arrival Details

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

Other System Modifications

This spyware modifies the following files:

  • %System%\drivers\etc\hosts

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths
Directory = "%Temporary Internet Files%\Content.IE5"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths
Paths = "4"

(Note: The default value data of the said registry entry is 4.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path1
CachePath = "%Temporary Internet Files%\Content.IE5\Cache1"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache1.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path2
CachePath = "%Temporary Internet Files%\Content.IE5\Cache2"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache2.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path3
CachePath = "%Temporary Internet Files%\Content.IE5\Cache3"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache3.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path4
CachePath = "%Temporary Internet Files%\Content.IE5\Cache4"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache4.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path1
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path2
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path3
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path4
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
ProxyEnable = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Connections
SavedLegacySettings = "{random values}"

(Note: The default value data of the said registry entry is {random values}.)

Dropping Routine

This spyware drops the following files:

  • %System%\puta.dll
  • %System%\cdftmong.exe
  • %Windows%\cdfongt.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.200

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Restore this modified registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths
    • From: Directory = "%Temporary Internet Files%\Content.IE5"
      To: Directory = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths
    • From: Paths = "4"
      To: Paths = ""4""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache1"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache1""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache2"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache2""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache3"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache3""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache4"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache4""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
    • ProxyEnable = "0"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections
    • From: SavedLegacySettings = "{random values}"
      To: SavedLegacySettings = ""{random values}""

Step 3

Search and delete these files

[ Learn More ]
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %System%\puta.dll
  • %System%\cdftmong.exe
  • %Windows%\cdfongt.exe

Step 4

Scan your computer with your Trend Micro product to delete files detected as TSPY_BANCOS.IK. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

Step 5

Restore deleted/modified files and/or registry entries from backup

*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

    • %System%\drivers\etc\hosts


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