BKDR_RSLAVE.A
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This backdoor connects to a certain URL to send and receive commands from a remote malicious user. It is capable of executing the certain backdoor commands. It also performs a HTTP POST request. However, as of this writing, the server does not respond to the request.
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 may be downloaded by other malware/grayware/spyware from remote sites.
It does not have any propagation routine.
TECHNICAL DETAILS
Varies
EXE
Yes
26 Jul 2011
Compromises system security, Connects to URLs/IPs
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.
It may be downloaded by other malware/grayware/spyware from remote sites.
Other System Modifications
This backdoor adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
IE8RunLastRead = "4e3152a2"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
IE8RunLastDraft = "4e3152a2"
Propagation
This backdoor does not have any propagation routine.
Backdoor Routine
This backdoor connects to the following URL(s) to send and receive commands from a remote malicious user:
- {BLOCKED}u.xxuz.com
NOTES:
It is capable of executing the following backdoor commands:
- Download and execute other possibly malicious file(s) from the Internet
- Restart itself
- Steal information related to Gmail (user name, password, etc.)
- Terminate itself
It sends the following information to its C&C server:
- Computer name
- IP address
- User name
- Windows version
- Information related to Gmail (user name, password, etc.)
It also performs the following HTTP POST request:
- http://{BLOCKED}u.xxuz.com/ym/Attachments?YY={parameters}
As of this writing, the server does not respond to the request.
It does not have rootkit capabilities.
It does not exploit any vulnerability.
SOLUTION
8.900
8.316.11
28 Jul 2011
8.317.00
28 Jul 2011
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Identify and terminate files detected as BKDR_RSLAVE.A
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 3
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\Internet Explorer\Main
- IE8RunLastRead = "4e3152a2"
- IE8RunLastRead = "4e3152a2"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
- IE8RunLastDraft = "4e3152a2"
- IE8RunLastDraft = "4e3152a2"
Step 4
Scan your computer with your Trend Micro product to delete files detected as BKDR_RSLAVE.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.
Did this description help? Tell us how we did.