Analysis by: RonJay Kristoffer Caragay
ALIASES:

JAVA/Qrat.b (McAfee); Trojan.Maljava (Symantec); Mal/JavaJar-A (Sophos); a variant of Java/Kryptik.C (ESET-NOD32);

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This backdoor 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

Tamaño del archivo 88,547 bytes
Tipo de archivo JAR
Residente en memoria Yes
Fecha de recepción de las muestras iniciales 10 Aug 2015

Arrival Details

This backdoor 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 backdoor drops the following copies of itself into the affected system and executes them:

  • %Application Data%\syslogdata\syslog-Agent.jar

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It drops the following files:

  • %Application Data%\syslogdata\blockedAgentMacAddresses
  • %Application Data%\syslogdata\macidAgent
  • %Application Data%\syslogdata\lastAgentMacAddresses

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It creates the following folders:

  • %Application Data%\syslogdata
  • %Application Data%\syslogdata\exc
  • %Application Data%\syslogdata\lib
  • %Application Data%\syslogdata\macnames
  • %Application Data%\syslogdata\pluginsAgent
  • %Application Data%\syslogdata\tempAgent

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
QRat-StartUp-Command = ""{Java installation folder}\javaw.exe" -jar "%Application Data%\syslogdata\syslog-Agent.jar" manageragent"

Other Details

This backdoor connects to the following possibly malicious URL:

  • {BLOCKED}ye.com
  • {BLOCKED}n.co
  • {BLOCKED}e.com
  • {BLOCKED}s.com.ru
  • {BLOCKED}a.com