TROJ_UPATRE.YYLK

 Analysis by: RonJay Kristoffer Caragay

 ALIASES:

TrojanDownloader:Win32/Upatre.AB (Microsoft); RDN/Generic Downloader.x!kf (McAfee); Downloader.Upatre (Symantec); Trojan-Downloader.Win32.Agent.helr (Kaspersky); Troj/Upatre-BZ (Sophos); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Downloader.Generic13.CDNZ (AVG)

 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:
 INFORMATION EXPOSURE:

  • 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.

It deletes itself after execution.

  TECHNICAL DETAILS

File Size:

20,992 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

23 May 2014

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.

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\srris.exe

(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.)

Download Routine

This Trojan saves the files it downloads using the following names:

  • %User Temp%\mango.exe

(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.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}mpany.com/images/Targ-1505USdw.tar

It deletes itself after execution.