TROJ_IESER.AB
TrojanDownloader:Win32/Delf.TV (Microsoft); Generic.dx (McAfee); Trojan.Dropper (Symantec); PAK:PE_Patch.PECompact, PAK:PecBundle, PAK:PECompact, Trojan-Downloader.Win32.Ieser.z (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.586544 (FSecure)
Windows 2000, Windows XP, Windows Server 2003
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
309,252 bytes
EXE
No
28 Apr 2012
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.
Autostart Technique
This Trojan registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry keys:
HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{16C6167B-FED4-4CEE-8951-134C9A345DA2}
Other System Modifications
This Trojan deletes the following files:
- AUTOEXEC.BAT
- boot.ini
- CONFIG.SYS
- Documents and Settings
- IO.SYS
- MSDOS.SYS
- NTDETECT.COM
- ntldr
- pagefile.sys
- Program Files
- RECYCLER
- sysprep.inf
- System Volume Information
- vcredist_x86.exe
- WINDOWS
It adds the following registry keys:
HKEY_CLASSES_ROOT\CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}
HKEY_CLASSES_ROOT\CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}\
InprocServer32
HKEY_CLASSES_ROOT\immdtqupui.TIEBHOCom
HKEY_CLASSES_ROOT\immdtqupui.TIEBHOCom\Clsid
HKEY_CLASSES_ROOT\CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}\
ProgID
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}\InprocServer32
ThreadingModel = "Apartment"
Dropping Routine
This Trojan drops the following files:
- %System%\immdtqupui.dll
- %System%\sssss.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
This report is generated via an automated analysis system.
SOLUTION
9.200
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
Close all opened browser windows
Step 3
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_CLASSES_ROOT\CLSID
- {16C6167B-FED4-4CEE-8951-134C9A345DA2}
- In HKEY_CLASSES_ROOT\CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}
- InprocServer32
- In HKEY_CLASSES_ROOT
- immdtqupui.TIEBHOCom
- In HKEY_CLASSES_ROOT\immdtqupui.TIEBHOCom
- Clsid
- In HKEY_CLASSES_ROOT\CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}
- ProgID
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_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{16C6167B-FED4-4CEE-8951-134C9A345DA2}\InprocServer32
- ThreadingModel = "Apartment"
Step 5
Search and delete these files
- %System%\immdtqupui.dll
- %System%\sssss.exe
Step 6
Scan your computer with your Trend Micro product to delete files detected as TROJ_IESER.AB. 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.
Step 7
Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.
- AUTOEXEC.BAT
- boot.ini
- CONFIG.SYS
- Documents and Settings
- IO.SYS
- MSDOS.SYS
- NTDETECT.COM
- ntldr
- pagefile.sys
- Program Files
- RECYCLER
- sysprep.inf
- System Volume Information
- vcredist_x86.exe
- WINDOWS
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