TROJ_DOFOIL.QS
T rojan-Downloader.Win32.Dofoil.qto (Kaspersky); TrojanDownloader:Win32/Kuluoz.B (Microsoft)
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: Trojan
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
This Trojan 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
45,056 bytes
EXE
Yes
10 Aug 2013
Connects to URLs/IPs
Arrival Details
This Trojan 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 Trojan drops the following files:
- %Application Data%\{random filename}.txt
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
It drops the following copies of itself into the affected system:
- %Application Data%\{random filename}.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
It injects itself into the following processes as part of its memory residency routine:
- svchost.exe
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random value} = "%Application Data%\{random filename.exe}"
Other System Modifications
This Trojan adds the following registry entries as part of its installation routine:
HKEY_CURRENT_USER\Software\{random value}
{random value} = "{random value}"
Download Routine
This Trojan accesses the following websites to download files:
- {BLOCKED}.1.231:8080
- {BLOCKED}.80.201:8080
- {BLOCKED}.96.181:8080
- {BLOCKED}.65.66:443
SOLUTION
9.300
10.214.06
10 Aug 2013
10.214.00
13 Aug 2013
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 TROJ_DOFOIL.QS
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\{random value}
- {random value} = "{random value}"
- {random value} = "{random value}"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- {random value} = "%Application Data%\{random filename.exe}"
- {random value} = "%Application Data%\{random filename.exe}"
Step 5
Search and delete this file
- %Application Data%\{random filename}.txt
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DOFOIL.QS. 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.