BKDR_ANDROM.FCC
Win32/TrojanDownloader.Wauchos.I trojan (ESET)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
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.
It executes then deletes itself afterward.
TECHNICAL DETAILS
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:
- %All Users Profile%\{random file name}.exe
- %All Users Profile%\svchost.exe
(Note: %All Users Profile% is the All Users or Common profile folder, which is C:\Documents and Settings\All Users in Windows 2000, XP, and Server 2003, and C:\ProgramData in Windows Vista and 7.)
It executes then deletes itself afterward.
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
SunJavaUpdateSched = "%All Users Profile%\svchost.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
{random number} = "%All Users Profile%\{random file name}.exe"
Other System Modifications
This backdoor adds the following registry keys as part of its installation routine:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
It creates the following registry entry(ies) to bypass Windows Firewall:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\msiexec.exe = "%System%\msiexec.exe:*:Generic Host Process"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\svchost.exe = "%System%\svchost.exe:*:Generic Host Process"
Other Details
This backdoor connects to the following possibly malicious URL:
- http://{BLOCKED}k.me/dns_test/test_results.php