TROJ_SWISYN.AA

July 16, 2013
 Modified by: Sabrina Lei Sioting
 ALIASES:

TrojanProxy:Win32/Small.DY (Microsoft), W32/Swisyn.WIA!tr (Fortinet),

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

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 executes the files it drops, prompting the affected system to exhibit the malicious routines they contain.

However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

409,600 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

25 Oct 2009

Payload:

Connects to URLs/IPs

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 adds the following mutexes to ensure that only one of its copies runs at any one time:

  • ZonesCounterMutex
  • ZonesLockedCacheCounterMutex

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
Windows Defender = "{malware path}\{malware name}.exe"

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\services.exe - detected as TROJ_PROXY.OR

(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 executes the files it drops, prompting the affected system to exhibit the malicious routines they contain.

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}hnaya.000page.com/g.php?h={hex numbers}&p={numbers}
  • http://{BLOCKED}hnaya.heyup.me/g.php?h={hex numbers}&p={numbers}
  • http://{BLOCKED}li.host.putidea.co.cc/g.php?h={hex numbers}&p={numbers}
  • http://{BLOCKED}-will.getenjoyment.net/g.php?h={hex numbers}&p={numbers}

However, as of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

7.738.05

FIRST VSAPI PATTERN DATE:

31 Dec 2010

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

Remove the malware/grayware file dropped/downloaded by TROJ_SWISYN.AA

    TROJ_PROXY.OR

Step 3

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
    • Windows Defender = "{malware path}\{malware name}.exe"

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_SWISYN.AA. 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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