BKDR_SYSIE.A
Windows 2000, Windows XP, Windows Server 2003, Windows Vista, Windows 7
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
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 commands from a remote malicious user, effectively compromising the affected system.
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 component file(s):
- {malware path}\cfg.dat - malware's configuration file
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
{malware filename}.exe = "{malware path}\{malware filename}.exe"
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Capture screen shots
- Download files
- Upload files
- Enumerate files and folders
- Execute files
- Get default internet browser
- Navigate and open a URL in a hidden browser
- Log user keystrokes and mouse clicks
- Update self
- Update configuration file
- Update bulletin thread used
- Sleep for a specified amount of time
- Remove self from system
Other Details
This backdoor uploads files to the following website(s):
- http://{BLOCKED}k.{BLOCKED}t.me/upld.php
NOTES:
It connects to the following Bulletin Board Systems (BBSs) to send and receive commands from a remote malicious user.
- http://{BLOCKED}s.{BLOCKED}or.jp/bbs/{BLOCKED}.cgi/{boardCat}/{bbsID}/{threadID}/
- http://{BLOCKED}s.{BLOCKED}or.jp/bbs/{BLOCKED}.cgi/{boardCat}/{bbsID}/
The board category, BBS id, and upload URL it uses depends on the contents of its configuration file cfg.dat.
SOLUTION
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
Scan your computer with your Trend Micro product and note files detected as BKDR_SYSIE.A
Step 3
Restart in Safe Mode
Step 4
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- {malware filename}.exe = "{malware path}\{malware filename}.exe"
- {malware filename}.exe = "{malware path}\{malware filename}.exe"
Step 5
Search and delete this file
- {malware path}\cfg.dat
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_SYSIE.A. 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.
NOTES:
Step 3 To restart in Safe Mode:
- For Windows Vista and Windows 7 users
- Restart your computer.
- Press F8 after the Power-On Self Test (POST) routine is done. If the Advanced Boot Options menu does not appear, try restarting then pressing F8 several times when the POST screen appears.
- On the Advanced Boot Options menu, use the arrow keys to select Safe Mode then press Enter.
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