BKDR_XYLIGAN.BT
Backdoor:Win32/Xyligan.A (Microsoft); RDN/Generic BackDoor!gn (McAfee); Backdoor.Win32.Xyligan.ahrh (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Downloader.Generic_r.OO (AVG)
Windows 2000, Windows XP, Windows Server 2003
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 deletes itself after execution.
TECHNICAL DETAILS
423,936 bytes
EXE
No
29 May 2013
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:
- %System%\kfliiu.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)
It creates the following folders:
- %User Profile%\Application Data\DYA_IFOTAQCQWOQORVWJA
- %User Profile%\DYA_IFOTAQCQWOQORVWJA\1.0.0
- %User Profile%\1.0.0\Data
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)
Other System Modifications
This backdoor adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\5up454i56ty1h56h
Description = "5l56g1515h15er5gssg1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\kfliiu.exe = "%System%\kfliiu.exe:*:Enabled:Microsoft (R) Internetal IExplore"
Dropping Routine
This backdoor drops the following files:
- %User Profile%\Data\app.dat
- %User Profile%\Data\updates.dat
- %User Profile%\Data\dya.dat
- %User Profile%\Application Data:$SS_DESCRIPTOR_SBXNV9VVGV1BFMF46G4XJG6G6XRT9WFNETMWYK0FSVF7VB4VPJGF
- %User Profile%\DYA_IFOTAQCQWOQORVWJA\1.0.0:$SS_DESCRIPTOR_SBXNV9VVGV1BFMF46G4XJG6G6XRT9WFNETMWYK0FSVF7VB4VPJGF
- %Desktop%:$SS_DESCRIPTOR_SBXNV9VVGV1BFMF46G4XJG6G6XRT9WFNETMWYK0FSVF7VB4VPJGF
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %Desktop% is the current user's desktop, which is usually C:\Documents and Settings\{User Name}\Desktop on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\Desktop on Windows Vista and 7.)
Other Details
This backdoor deletes itself after execution.
This report is generated via an automated analysis system.
SOLUTION
9.300
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\5up454i56ty1h56h
- Description = "5l56g1515h15er5gssg1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- %System%\kfliiu.exe = "%System%\kfliiu.exe:*:Enabled:Microsoft (R) Internetal IExplore"
Step 3
Search and delete these components
- %User Profile%\Data\app.dat
- %User Profile%\Data\updates.dat
- %User Profile%\Data\dya.dat
- %User Profile%\Application Data:$SS_DESCRIPTOR_SBXNV9VVGV1BFMF46G4XJG6G6XRT9WFNETMWYK0FSVF7VB4VPJGF
- %User Profile%\DYA_IFOTAQCQWOQORVWJA\1.0.0:$SS_DESCRIPTOR_SBXNV9VVGV1BFMF46G4XJG6G6XRT9WFNETMWYK0FSVF7VB4VPJGF
- %Desktop%:$SS_DESCRIPTOR_SBXNV9VVGV1BFMF46G4XJG6G6XRT9WFNETMWYK0FSVF7VB4VPJGF
Step 4
Search and delete these folders
- %User Profile%\Application Data\DYA_IFOTAQCQWOQORVWJA
- %User Profile%\DYA_IFOTAQCQWOQORVWJA\1.0.0
- %User Profile%\1.0.0\Data
Step 5
Scan your computer with your Trend Micro product to delete files detected as BKDR_XYLIGAN.BT. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
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