TROJ_KRYPTIK.CX
PWS:Win32/Fareit.gen!C (Microsoft); PWS-Zbot.gen.uh (McAfee); Trojan.ADH (Symantec); Packed.Win32.Krap.iu (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt)
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.
It deletes itself after execution.
TECHNICAL DETAILS
130,528 bytes
EXE
Yes
19 Jun 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.
Installation
This Trojan creates the following folders:
- %User Profile%\Application Data\Muzio
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)
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
{58C4EBA0-47A8-AD40-8C85-A85A94978B48} = "%User Profile%\Muzio\afaqeq.exe"
Other System Modifications
This Trojan deletes the following files:
- %User Profile%\Cookies\administrator@ad.wsod[2].txt
- %User Profile%\Cookies\administrator@atdmt[2].txt
- %User Profile%\Cookies\administrator@bing[2].txt
- %User Profile%\Cookies\administrator@c.msn[1].txt
- %User Profile%\Cookies\administrator@microsoft[1].txt
- %User Profile%\Cookies\administrator@msn[1].txt
- %User Profile%\Cookies\administrator@scorecardresearch[1].txt
- %User Profile%\Cookies\administrator@www.bing[1].txt
- %User Profile%\Cookies\administrator@www.msn[1].txt
It adds the following registry keys:
HKEY_CURRENT_USER\Software\WinRAR
HKEY_CURRENT_USER\Software\Microsoft\
Unzoex
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Privacy
It adds the following registry entries:
HKEY_CURRENT_USER\Software\WinRAR
HWID = "{random values}"
HKEY_CURRENT_USER\Software\WinRAR
Client Hash = "{random values}"
HKEY_CURRENT_USER\Software\WinRAR
39CDF6844FF19B656B7CD456B7B37D0E = "{random values}"
HKEY_CURRENT_USER\Software\WinRAR
17801C540592B1916F7FDF0E6EC1D15C = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager
Server ID = "4"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
FirstRun = "1"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
OlkContactRefresh = "0"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
OlkFolderRefresh = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Unzoex
2f27ag2a = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Privacy
CleanCookies = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DisableNotifications = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
28070:UDP = "28070:UDP:*:Enabled:UDP 28070"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DisableNotifications = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
27441:TCP = "27441:TCP:*:Enabled:TCP 27441"
HKEY_CURRENT_USER\Software\Microsoft\
Unzoex
1abge8d4 = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
Unzoex
2abde0b0 = "nKF0bg==_CHAR(0x03)__CHAR(0x03)_s?S???"
HKEY_CURRENT_USER\Software\Microsoft\
Unzoex
2abde0b0 = "{random values}"
It modifies the following registry entries:
HKEY_CURRENT_USER\Identities
Last Username = "Main Identity"
(Note: The default value data of the said registry entry is Main Identity.)
HKEY_CURRENT_USER\Identities
Last User ID = "{341F68BA-C841-4200-A7B4-3D5CFF202166}"
(Note: The default value data of the said registry entry is {C0FE0177-5693-4537-9331-A7402AD82D40}.)
HKEY_CURRENT_USER\Identities
Identity Login = "9853"
(Note: The default value data of the said registry entry is 98053.)
HKEY_CURRENT_USER\Identities
Identity Ordinal = "2"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\0
1609 = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\1
1406 = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\1
1609 = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\2
1609 = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1406 = "0"
(Note: The default value data of the said registry entry is 3.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1609 = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\4
1406 = "0"
(Note: The default value data of the said registry entry is 3.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\4
1609 = "0"
(Note: The default value data of the said registry entry is 1.)
Dropping Routine
This Trojan drops the following files:
- %User Temp%\57031.exe
- %User Temp%\59406.exe
- %User Temp%\64046.exe
- %User Profile%\Application Data\Muzio
- %User Profile%\Muzio\afaqeq.exe
- %Application Data%\alux.guj
(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.. %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.. %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
Other Details
This Trojan deletes itself after execution.
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
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
- WinRAR
- In HKEY_CURRENT_USER\Software\Microsoft
- Unzoex
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer
- Privacy
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
- {58C4EBA0-47A8-AD40-8C85-A85A94978B48} = "%User Profile%\Muzio\afaqeq.exe"
- In HKEY_CURRENT_USER\Software\WinRAR
- HWID = "{random values}"
- In HKEY_CURRENT_USER\Software\WinRAR
- Client Hash = "{random values}"
- In HKEY_CURRENT_USER\Software\WinRAR
- 39CDF6844FF19B656B7CD456B7B37D0E = "{random values}"
- In HKEY_CURRENT_USER\Software\WinRAR
- 17801C540592B1916F7FDF0E6EC1D15C = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager
- Server ID = "4"
- In HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4
- FirstRun = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4
- OlkContactRefresh = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4
- OlkFolderRefresh = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Unzoex
- 2f27ag2a = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Privacy
- CleanCookies = "0"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
- DisableNotifications = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 28070:UDP = "28070:UDP:*:Enabled:UDP 28070"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
- DisableNotifications = "0"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 27441:TCP = "27441:TCP:*:Enabled:TCP 27441"
- In HKEY_CURRENT_USER\Software\Microsoft\Unzoex
- 1abge8d4 = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\Unzoex
- 2abde0b0 = "nKF0bg==_CHAR(0x03)__CHAR(0x03)_s?S???"
- In HKEY_CURRENT_USER\Software\Microsoft\Unzoex
- 2abde0b0 = "{random values}"
Step 5
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_CURRENT_USER\Identities
- From: Last Username = "Main Identity"
To: Last Username = ""Main Identity""
- From: Last Username = "Main Identity"
- In HKEY_CURRENT_USER\Identities
- From: Last User ID = "{341F68BA-C841-4200-A7B4-3D5CFF202166}"
To: Last User ID = ""{C0FE0177-5693-4537-9331-A7402AD82D40}""
- From: Last User ID = "{341F68BA-C841-4200-A7B4-3D5CFF202166}"
- In HKEY_CURRENT_USER\Identities
- From: Identity Login = "9853"
To: Identity Login = ""98053""
- From: Identity Login = "9853"
- In HKEY_CURRENT_USER\Identities
- From: Identity Ordinal = "2"
To: Identity Ordinal = ""1""
- From: Identity Ordinal = "2"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0
- From: 1609 = "0"
To: 1609 = ""1""
- From: 1609 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1
- From: 1406 = "0"
To: 1406 = ""1""
- From: 1406 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1
- From: 1609 = "0"
To: 1609 = ""1""
- From: 1609 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2
- From: 1609 = "0"
To: 1609 = ""1""
- From: 1609 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
- From: 1406 = "0"
To: 1406 = ""3""
- From: 1406 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
- From: 1609 = "0"
To: 1609 = ""1""
- From: 1609 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
- From: 1406 = "0"
To: 1406 = ""3""
- From: 1406 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
- From: 1609 = "0"
To: 1609 = ""1""
- From: 1609 = "0"
Step 6
Search and delete these files
- %User Temp%\57031.exe
- %User Temp%\59406.exe
- %User Temp%\64046.exe
- %User Profile%\Application Data\Muzio
- %User Profile%\Muzio\afaqeq.exe
- %Application Data%\alux.guj
Step 7
Search and delete this folder
- %User Profile%\Application Data\Muzio
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_KRYPTIK.CX. 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.
- %User Profile%\Cookies\administrator@ad.wsod[2].txt
- %User Profile%\Cookies\administrator@atdmt[2].txt
- %User Profile%\Cookies\administrator@bing[2].txt
- %User Profile%\Cookies\administrator@c.msn[1].txt
- %User Profile%\Cookies\administrator@microsoft[1].txt
- %User Profile%\Cookies\administrator@msn[1].txt
- %User Profile%\Cookies\administrator@scorecardresearch[1].txt
- %User Profile%\Cookies\administrator@www.bing[1].txt
- %User Profile%\Cookies\administrator@www.msn[1].txt
Did this description help? Tell us how we did.