JAVA_KRYPTIK.NNG
JAVA/Qrat.b (McAfee); Trojan.Maljava (Symantec); Mal/JavaJar-A (Sophos); a variant of Java/Kryptik.C (ESET-NOD32);
Windows
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
88,547 bytes
JAR
Yes
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