TROJ_ESAPROF.AH
TrojanDownloader:Win32/Esaprof.A(Microsoft), Trojan-Downloader.Win32.Esaprof(Ikarus), SWF/TrojanDownloader.Esaprof.A 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: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
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
3,940,206 bytes
EXE
Yes
04 Feb 2014
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:
- %User Temp%\wrd-{random}.~lk\0.mdd
- %User Temp%\wrd-{random}.~lk\1.mdd
- %User Temp%\wrd-{random}.~lk\2.mdd
- %User Temp%\wrd-{random}.~lk\3.mdd
- %User Temp%\wrd-{random}.~lk\4.mdd
- %User Temp%\wrd-{random}.~lk\~swd1.dat
- %User Temp%\wrd-{random}.~lk\~swd1.swf
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)
It drops the following copies of itself into the affected system:
- %Start Menu%\Programs\{malware file name}.exe
(Note: %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu on Windows Vista and 7.)
It creates the following folders:
- %User Temp%\wrd-{random}.~lk
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)
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
Startup = %Start Menu%\Programs\{malware file name}.exe"
Other System Modifications
This Trojan adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Speech\Voices
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplications
Name = "{malware file name}.exe"
(Note: The default value data of the said registry entry is {application}.)
SOLUTION
9.700
10.584.03
04 Feb 2014
10.585.00
04 Feb 2014
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_ESAPROF.AH
Step 3
Terminate a process file/s detected as TROJ_ESAPROF.AH
*Note: If the detected file/s is/are not displayed in theWindows Task Manager, continue doing the next steps.
Step 4
Delete this registry key
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\Speech
- Voices
- Voices
Step 5
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
- Startup = "%Start Menu%\Programs\{malware file name}.exe"
- Startup = "%Start Menu%\Programs\{malware file name}.exe"
Step 6
Restore this modified 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\SOFTWARE\Microsoft\DirectDraw\MostRecentApplications
- From: Name = "{malware file name}.exe"
To: Name = {application}
- From: Name = "{malware file name}.exe"
Step 7
Search and delete these folders
- %User Temp%\wrd-{random}.~lk
Step 8
Scan your computer with your Trend Micro product to delete files detected as TROJ_ESAPROF.AH. 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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