Analysis by: Sabrina Lei Sioting
 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  TECHNICAL DETAILS

File Size: 69,608 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 28 Sep 2010
Payload: Connects to URLs/Ips

Installation

This Trojan drops the following copies of itself into the affected system:

  • %Windows%\jusched.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Java developer Script Browse = %Windows%\jusched.exe

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Java developer Script Browse = %Windows%\jusched.exe

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Terminal Server\
Install\Software\Microsoft\
Windows\CurrentVersion\Run
Java developer Script Browse = %Windows%\jusched.exe

Other System Modifications

This Trojan adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Terminal Server\
Install

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Terminal Server\
Install\Software

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Terminal Server\
Install\Software\Microsoft\
Windows

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Terminal Server\
Install\Software\Microsoft\
Windows\CurrentVersion

It creates the following registry entry(ies) to bypass Windows Firewall:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\FirewallRules
{6A96B708-94D3-4AF9-BC1D-4E8E1CA6DF94} = v2.10|Action=Allow|Active=TRUE|Dir=In|Protocol=17|Profile=Public|App={malware path and name}|Name=1|

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
{malware path and name} = %Windows%\jusched.exe:*:Enabled:Java developer Script Browse

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\FirewallRules
{3019A387-97B0-4E7D-A146-81304E7F8647} = v2.10|Action=Allow|Active=TRUE|Dir=In|Protocol=6|Profile=Public|App={malware path and name}|Name=1|

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}users.myspace.com/Browse/Browse.aspx - nonmalicious

  SOLUTION

Minimum Scan Engine: 8.900
VSAPI PATTERN File: 7.494.15
VSAPI PATTERN Date: 28 Sep 2010
VSAPI PATTERN Date: 9/28/2010 12:00:00 AM

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

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\Windows\CurrentVersion\Run
    • Java developer Script Browse=%Windows%\jusched.exe
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • Java developer Script Browse=%Windows%\jusched.exe
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\Run
    • Java developer Script Browse=%Windows%\jusched.exe
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\FirewallRules
    • {6A96B708-94D3-4AF9-BC1D-4E8E1CA6DF94}=v2.10|Action=Allow|Active=TRUE|Dir=In|Protocol=17|Profile=Public|App={malware path and name}|Name=1|
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • {malware path and name}=%Windows%\jusched.exe:*:Enabled:Java developer Script Browse
  • InHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\FirewallRules
    • {3019A387-97B0-4E7D-A146-81304E7F8647}=v2.10|Action=Allow|Active=TRUE|Dir=In|Protocol=6|Profile=Public|App={malware path and name}|Name=1|

Step 3

Delete this registry key

[ 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 NT\CurrentVersion\Terminal Server\
    • Install

Step 4

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