TROJ_VCARED.KS

 Analysis by: Jasen Sumalapao

 ALIASES:

Trojan:Win32/Vcaredrix.A (Microsoft), PAK:ASPack (Kaspersky), Trojan Horse (Symantec), Generic.dx!bfb4 (NAI), Troj/Scar-BS (Sophos), Trojan.Generic.KDV.673369 (FSecure), Trojan.Win32.Scar.ba (v) (Sunbelt), TR/Vcaredrix.A.3 (Antivir), Trojan.Generic.KDV.673369 (Bitdefender), PUA.Win32.Packer.Asprotect-2 (Clamav), W32/Scar.BS!tr (Fortinet), Trojan.Win32.Vcaredrix (Ikarus), Win32/Vcaredrix.A trojan (NOD32), Generic (Panda)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, Downloaded from the Internet


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 creates folders where it drops its files. It is injected into all running processes to remain memory resident.

It deletes the initially executed copy of itself.

It receives commands from a server that may be controlled by a bot or a malicious user.

  TECHNICAL DETAILS

File Size:

131,072 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

17 Jul 2012

Payload:

Connects to URLs/IPs, Steals information, Displays ads

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 drops a copy of itself in the following folders using different file names:

  • %User Profile%\Application Data\xsecva\xsecva.exe

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

It creates the following folders:

  • %User Profile%\Application Data\xsecva

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

It is injected into all running processes to remain memory resident.

It terminates the execution of the copy it initially executed and executes the copy it drops instead.

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
XSECVA = %User Profile%\Application Data\xsecva\xsecva.exe -s

Adware Routine

This Trojan connects to the following URL(s) to display ads on the affected system:

  • http://{BLOCKED}v.{BLOCKED}l.com/
  • http://{BLOCKED}d.{BLOCKED}raffic.com/feed.php
  • http://{BLOCKED}y.{BLOCKED}rdr.com/

Information Theft

This Trojan gathers the following data:

  • User's IP address
  • Current Country
  • Inputted Keywords
  • Accessed URLs

Other Details

Internet activities are monitored by a malicious user.

It deletes the initially executed copy of itself

Denial of Service

This Trojan receives commands from a server that may be controlled by a bot or a malicious user.

NOTES:

This Trojan connects from the server http://{BLOCKED}a.net/, which may be controlled by a bot or a malicious user.

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

9.266.07

FIRST VSAPI PATTERN DATE:

17 Jul 2012

VSAPI OPR PATTERN File:

9.267.00

VSAPI OPR PATTERN Date:

18 Jul 2012

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

Restart in Safe Mode

[ Learn More ]

Step 3

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Profile%\Application Data\xsecva

Step 4

Delete this 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\Run
    • XSECVA = "%User Profile%\Application Data\xsecva\xsecva.exe -s"

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_VCARED.KS. 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.


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