TROJ_ZBOT.HOM
PWS:Win32/Zbot.gen!AF (Microsoft); PWS-Zbot.gen.hz (McAfee); PAK:UPX, Trojan-Spy.Win32.Zbot.coyj (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.KDV.414673 (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.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
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\Jomoke
- %User Profile%\Application Data\Ynto
(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%\Jomoke\arud.exe""
It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
Other System Modifications
This Trojan adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Emvu
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Privacy
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Emvu
bi42e73 = 2365e4b8
HKEY_CURRENT_USER\Software\Microsoft\
Emvu
gefba81 = "jOQEI0nLlzK1uEG7GjMxe75KGtw1Zv6T? ?"
HKEY_CURRENT_USER\Software\Microsoft\
Emvu
bi42e73 = {random values}
HKEY_CURRENT_USER\Software\Microsoft\
Emvu
bi42e73 = "8ORlIw==e_CHAR(0x03)_O_CHAR(0x0C)__CHAR(0x01)_"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DisableNotifications = 1
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
23012:UDP = "23012:UDP:*:Enabled:UDP 23012"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
22953:TCP = "22953:TCP:*:Enabled:TCP 22953"
HKEY_CURRENT_USER\Software\Microsoft\
Emvu
2030j1i3 = "Bb1lI46S7jLYuC67_CHAR(0x03)__CHAR(0x05)_?_CHAR(0x08)_?"
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\
Emvu
bi42e73 = "sORlIw==¯_CHAR(0x03)__CHAR(0x17)__CHAR(0x0E)_?ã?ãunt name: income.account.com
E-mail: rsa@account.com
POP3:
Server: income.account.com:110
Username: rsa
Password: ÿÿÿÿÈôï
SMTP:
Server: outcome.account.com:25
Username:
Password:
"
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 {5D1D9894-914A-4AF9-BD82-81F349A83013}.)
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.)
Dropping Routine
This Trojan drops the following files:
- %User Profile%\Jomoke\arud.exe
- %User Profile%\Ynto\koex.epe
(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.)
Other Details
This Trojan deletes the initially executed copy of itself
This report is generated via an automated analysis system.
SOLUTION
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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts
- List
- In HKEY_CURRENT_USER\Software\Microsoft
- Emvu
- 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%\Jomoke\arud.exe""
- In HKEY_CURRENT_USER\Software\Microsoft\Emvu
- bi42e73=2365e4b8
- In HKEY_CURRENT_USER\Software\Microsoft\Emvu
- gefba81="jOQEI0nLlzK1uEG7GjMxe75KGtw1Zv6T? ?"
- In HKEY_CURRENT_USER\Software\Microsoft\Emvu
- bi42e73={random values}
- In HKEY_CURRENT_USER\Software\Microsoft\Emvu
- bi42e73="8ORlIw==e_CHAR(0x03)_O_CHAR(0x0C)__CHAR(0x01)_"
- 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
- 23012:UDP="23012:UDP:*:Enabled:UDP 23012"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 22953:TCP="22953:TCP:*:Enabled:TCP 22953"
- In HKEY_CURRENT_USER\Software\Microsoft\Emvu
- 2030j1i3="Bb1lI46S7jLYuC67_CHAR(0x03)__CHAR(0x05)_?_CHAR(0x08)_?"
- 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\Emvu
- bi42e73="sORlIw==¯_CHAR(0x03)__CHAR(0x17)__CHAR(0x0E)_?ã?ãunt name: income.account.com E-mail: rsa@account.com POP3: Server: income.account.com:110 Username: rsa Password: ÿÿÿÿÈôï SMTP: Server: outcome.account.com:25 Username: Password: "
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={5D1D9894-914A-4AF9-BD82-81F349A83013}
- 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
Step 6
Search and delete these folders
- %User Profile%\Application Data\Jomoke
- %User Profile%\Application Data\Ynto
Step 7
Search and delete these files
- %User Profile%\Jomoke\arud.exe
- %User Profile%\Ynto\koex.epe
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_ZBOT.HOM. 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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