TROJ_AGENT.ABVX

May 26, 2013
 ALIASES:

Downloader-COJ (McAfee); Trojan.Win32.Agent.hzu (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); MemScan:Trojan.Generic.1848357 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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.

  TECHNICAL DETAILS

File Size:

551,873 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

17 Apr 2012

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.

Other System Modifications

This Trojan deletes the following files:

  • %User Temp%\temp.dat
  • %User Temp%\Hdr.tmp
  • %User Temp%\Name.vbs

(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.)

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts
AssociatedID = "{random values}"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager
Server ID = "4"

It modifies the following registry entries:

HKEY_CURRENT_USER\Identities
Last Username = "Main Identity"

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

HKEY_CURRENT_USER\Identities
Last User ID = "{341F68BA-C841-4200-A7B4-3D5CFF202166}"

(Note: The default value data of the said registry entry is {C0FE0177-5693-4537-9331-A7402AD82D40}.)

HKEY_CURRENT_USER\Identities
Identity Login = "9853"

(Note: The default value data of the said registry entry is 98053.)

HKEY_CURRENT_USER\Identities
Identity Ordinal = "2"

(Note: The default value data of the said registry entry is 1.)

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\Header.dat
  • %User Temp%\hdr.tmp
  • %User Temp%\file2.empty
  • %User Temp%\file3.empty
  • %User Temp%\file4.empty
  • %User Temp%\file5.empty
  • %User Temp%\file6.empty
  • %Favorites%/ÈÌß.url
  • %Desktop%\àíøà àáäóë.txt.txt
  • %Windows%\Report.txt
  • %Windows%\Net.vbs

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

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

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_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts
    • AssociatedID = "{random values}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager
    • Server ID = "4"

Step 3

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Identities
    • From: Last Username = "Main Identity"
      To: Last Username = ""Main Identity""
  • In HKEY_CURRENT_USER\Identities
    • From: Last User ID = "{341F68BA-C841-4200-A7B4-3D5CFF202166}"
      To: Last User ID = ""{C0FE0177-5693-4537-9331-A7402AD82D40}""
  • In HKEY_CURRENT_USER\Identities
    • From: Identity Login = "9853"
      To: Identity Login = ""98053""
  • In HKEY_CURRENT_USER\Identities
    • From: Identity Ordinal = "2"
      To: Identity Ordinal = ""1""

Step 4

Search and delete these components

[ Learn More ]
There may be some components 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.
  • %User Temp%\Header.dat
  • %User Temp%\hdr.tmp
  • %User Temp%\file2.empty
  • %User Temp%\file3.empty
  • %User Temp%\file4.empty
  • %User Temp%\file5.empty
  • %User Temp%\file6.empty
  • %Favorites%/ÈÌß.url
  • %Desktop%\àíøà àáäóë.txt.txt
  • %Windows%\Report.txt
  • %Windows%\Net.vbs

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_AGENT.ABVX. 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 6

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Temp%\temp.dat
  • %User Temp%\Hdr.tmp
  • %User Temp%\Name.vbs


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