Analysis by: Jasen Sumalapao
ALIASES:

Trojan:Win32/Rimecud.A (Microsoft), Trojan.Gen.2 (Symantec), W32/Rimecud.gen.dl (NAI), Mal/Rimecud-M (Sophos), Trojan.Win32.Encpk.adua (v) (Sunbelt), TR/Crypt.EPACK.Gen8 (Antivir), Gen:Variant.Barys.4479 (Bitdefender), W32/Kryptik.WEC!tr (Fortinet), Virus.Win32.Cryptor (Ikarus), a variant of Win32/Kryptik.AGPY trojan (NOD32), Trj/Rimecud.f (Panda)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This worm arrives by connecting affected removable drives to a system. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It drops copies of itself in all removable and physical drives found in the system. It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

  TECHNICAL DETAILS

File Size: 98,816 bytes
File Type: EXE
Initial Samples Received Date: 23 Aug 2012

Arrival Details

This worm arrives by connecting affected removable drives to a system.

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

  • %User Profile%\selqeq.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 injects itself into the following processes as part of its memory residency routine:

  • svchost.exe

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Taskman = %User Profile%\selqeq.exe

Propagation

This worm drops copies of itself in all removable and physical drives found in the system.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

Download Routine

This worm connects to the following website(s) to download and execute a malicious file:

  • portal.{BLOCKED}erbord.com
  • murik.{BLOCKED}tection.net.ru
  • slade.{BLOCKED}number.com
  • banana.{BLOCKED}nds.su
  • world.{BLOCKED}udio.ru