TROJ_MYCILSEA.A
Trojan.Gen.2 (Symantec)
Windows
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
8,895,488 bytes
EXE
Yes
11 Nov 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 copies of itself into the affected system:
- %User Temp%\Win Update\Win Update.exe
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It creates the following folders:
- %User Temp%\Win Update
- %User Profile%\Application Data\dclogs
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} 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
Win Update = "%User Temp%\Win Update\Win Update.exe"
Other System Modifications
This Trojan deletes the following files:
- {malware path and file name}:zone.identifier
It adds the following registry keys:
HKEY_CURRENT_USER\Software\DC3_FEXEC
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\
Default MidiOut Device
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\
Default DirectSound Device
HKEY_CURRENT_USER\Software\Microsoft\
Multimedia\ActiveMovie\Filter Cache
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\
Default MidiOut Device
FriendlyName = "Default MidiOut Device"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\
Default MidiOut Device
CLSID = "{07B65360-C445-11CE-AFDE-00AA006C14F4}"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\
Default MidiOut Device
FilterData = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\
Default MidiOut Device
MidiOutId = "ffffffff"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\
Default DirectSound Device
FriendlyName = "Default DirectSound Device"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\
Default DirectSound Device
CLSID = "{79376820-07D0-11CF-A24D-0020AFD79767}"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\
Default DirectSound Device
FilterData = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\
Default DirectSound Device
DSGuid = "{00000000-0000-0000-0000-000000000000}"
HKEY_CURRENT_USER\Software\Microsoft\
Multimedia\ActiveMovie\Filter Cache
0 = "{random values}"
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
MediaPlayer
MP2.SaveDir = "%Program Files%\Windows Media Player"
(Note: The default value data of the said registry entry is %Program Files%\Windows Media Player.)
It deletes the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\MUILanguages\
FileVersions
Dropping Routine
This Trojan drops the following files:
- %User Temp%\Eminem Ft. Rihanna - The Monster.mp3
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
Other Details
This Trojan connects to the following possibly malicious URL:
- {BLOCKED}.99.109
This report is generated via an automated analysis system.
SOLUTION
9.700
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
Restart in Safe Mode
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_CURRENT_USER\Software
- DC3_FEXEC
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum
- {4EFE2452-168A-11D1-BC76-00C04FB9453B}
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}
- Default MidiOut Device
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum
- {E0F158E1-CB04-11D0-BD4E-00A0C911CE86}
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}
- Default DirectSound Device
- In HKEY_CURRENT_USER\Software\Microsoft\Multimedia\ActiveMovie
- Filter Cache
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
- Win Update = "%User Temp%\Win Update\Win Update.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\Default MidiOut Device
- FriendlyName = "Default MidiOut Device"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\Default MidiOut Device
- CLSID = "{07B65360-C445-11CE-AFDE-00AA006C14F4}"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\Default MidiOut Device
- FilterData = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{4EFE2452-168A-11D1-BC76-00C04FB9453B}\Default MidiOut Device
- MidiOutId = "ffffffff"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\Default DirectSound Device
- FriendlyName = "Default DirectSound Device"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\Default DirectSound Device
- CLSID = "{79376820-07D0-11CF-A24D-0020AFD79767}"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\Default DirectSound Device
- FilterData = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\ActiveMovie\devenum\{E0F158E1-CB04-11D0-BD4E-00A0C911CE86}\Default DirectSound Device
- DSGuid = "{00000000-0000-0000-0000-000000000000}"
- In HKEY_CURRENT_USER\Software\Microsoft\Multimedia\ActiveMovie\Filter Cache
- 0 = "{random values}"
Step 5
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MediaPlayer
- From: MP2.SaveDir = "%Program Files%\Windows Media Player"
To: MP2.SaveDir = ""%Program Files%\Windows Media Player""
- From: MP2.SaveDir = "%Program Files%\Windows Media Player"
Step 6
Search and delete this file
- %User Temp%\Eminem Ft. Rihanna - The Monster.mp3
Step 7
Search and delete these folders
- %User Temp%\Win Update
- %User Profile%\Application Data\dclogs
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_MYCILSEA.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.
Step 9
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.
- {malware path and file name}:zone.identifier
Step 10
Restore these deleted registry keys/values from backup
*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\MUILanguages
- FileVersions
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