WORM_SDBOT.MAL
Backdoor:Win32/IRCbot.gen!K (Microsoft), W32.IRCBot.Gen (Symantec), W32/IRCBot.BAJ!tr.bdr (Fortinet), Generic.Sdbot.17D0BE32 (BitDefender)
Windows
Threat Type: Worm
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This worm arrives via removable drives. It 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
45,568 bytes
EXE
PECompact
Yes
14 Apr 2015
Arrival Details
This worm arrives via removable drives.
It 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 worm drops the following copies of itself into the affected system:
- %Windows%\system\slass.exe
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
It adds the following mutexes to ensure that only one of its copies runs at any one time:
- rtkjhi4568h96894H3G8H38958934hy9t3h498hy548hgmnhnf,ggsdfg4ww3333...
Autostart Technique
This worm registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\netmanlr
ObjectName = LocalSystem
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\netmanlr
Description = "Manage Local and Remote Network Connections Services. If this service is stopped, protected content might not be down loaded to the device."
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\netmanlr
ImagePath = "%Windows%\system\slass.exe"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\netmanlr
DisplayName = Network Connections Manage
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\netmanlr
Start = "2"
It adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Shell Extensions
systemxstuff = "{Malware path}\{Malware name}.exe"
Other System Modifications
This worm adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
EnableFirewall = "0"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wscsvc
Start = "4"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wuauserv
Start = "4"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess
Start = "2"
Propagation
This worm creates the following folders in all removable drives:
- {Removable drive letter except A and B}:\RECYCLER\S-1-6-21-2434476501-1644491937-600003330-1213
It drops the following copy(ies) of itself in all removable drives:
- {Removable drive letter except A and B}:\RECYCLER\S-1-6-21-2434476501-1644491937-600003330-1213\autorunme.exe
It uses the following user name and password to gain access to password-protected shares:
- "administrator"
- "administrador"
- "administrateur"
- "administrat"
- "admins"
- "admin"
- "adm"
- "password1"
- "password"
- "passwd"
- "pass1234"
- "pass"
- "pwd"
- "007"
- "12"
- "123"
- "1234"
- "12345"
- "123456"
- "1234567"
- "12345678"
- "123456789"
- "1234567890"
- "2000"
- "2001"
- "2002"
- "2003"
- "2004"
- "test"
- "guest"
- "none"
- "demo"
- "unix"
- "linux"
- "changeme"
- "default"
- "system"
- "server"
- "root"
- "null"
- "qwerty"
- "mail"
- "outlook"
- "web"
- "www"
- "internet"
- "accounts"
- "accounting"
- "home"
- "homeuser"
- "user"
- "oem"
- "oemuser"
- "oeminstall"
- "windows"
- "win98"
- "win2k"
- "winxp"
- "winnt"
- "win2000"
- "qaz"
- "asd"
- "zxc"
- "qwe"
- "bob"
- "jen"
- "joe"
- "fred"
- "bill"
- "mike"
- "john"
- "peter"
- "luke"
- "sam"
- "sue"
- "susan"
- "peter"
- "brian"
- "lee"
- "neil"
- "ian"
- "chris"
- "eric"
- "george"
- "kate"
- "bob"
- "katie"
- "mary"
- "login"
- "loginpass"
- "technical"
- "backup"
- "exchange"
- "fuck"
- "bitch"
- "slut"
- "sex"
- "god"
- "hell"
- "hello"
- "domain"
- "domainpass"
- "domainpassword"
- "database"
- "access"
- "dbpass"
- "dbpassword"
- "databasepass"
- "data"
- "databasepassword"
- "db1"
- "db2"
- "db1234"
- "sa"
- "sql"
- "sqlpassoainstall"
- "orainstall"
- "oracle"
- "ibm"
- "cisco"
- "dell"
- "compaq"
- "siemens"
- "hp"
- "nokia"
- "xp"
- "control"
- "office"
- "blank"
- "winpass"
- "main"
- "lan"
- "internet"
- "intranet"
- "student"
- "teacher"
- "staff"
Backdoor Routine
This worm connects to any of the following IRC server(s):
- oak.{BLOCKED}me.net
- {BLOCKED}.{BLOCKED}.179.100
- ringc.{BLOCKED}led.net
- {BLOCKED}arc.{BLOCKED}e.st
- gloves.{BLOCKED}o.org
- picc.{BLOCKED}s.net
- oak.{BLOCKED}me.net
- helms.{BLOCKED}o.org
- sandtp.{BLOCKED}nkiller.com
- computercc.{BLOCKED}list.com
- headmefc.{BLOCKED}As.com
- onthebreak.{BLOCKED}s.com
It joins any of the following IRC channel(s):
- #naga2
It accesses a remote Internet Relay Chat (IRC) server where it receives the following commands from a remote malicious user:
- Terminate itself
- Leave/join IRC channel
- Terminate itself
- Get list of currently running command threads
- Create/terminate threads
- Start/stop ddos attacks:
- udp flood
- tcp flood
- icmp flood
- bandwidth flood
- syn flood
- Perform ping command
- Visit websites using Internet Explorer
- Patches %System%\drivers\tcpip.sys as itself
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32. For 32-bit applications running under 64-bit system, this is usually C:\Windows\SysWOW64.) - Perform IRC commands
- Gathers information of the affected system:
- hostname
- host address
- Make an affected system the IRC server
- Flush DNS cache
- Get the IP address of the affected system using the following urls:
- http://checkip.dyndns.org
- http://checkip.dyndns.com
- http://checkip.dyndns.org:8245
- http://checkrealip.com
- http://www.ip138.com/ips8.asp
- http://www.canaan-it.net
- Scan for open ports either sequentially or randomly
- Adds/Deletes user in network Administrator group
Dropping Routine
This worm drops the following files:
- {Removable drive letter except A and B}:\autorun.inf
- {Removable drive letter except A and B}:\RECYCLER\S-1-6-21-2434476501-1644491937-600003330-1213\Desktop.ini
Information Theft
This worm gathers the following data:
- OS Version Info
- OS Service Pack
- OS Locale Info
- Computer Name
Other Details
This worm does the following:
- Terminates itself if the affected system's username is any of the following:
- CurrentUser
- Crrentuser
- Honey
- Sandbox
- VMWare
- Terminates itself if the currently running malware's name is:
- sample.exe
- Terminates itself if the following modules are present/loaded:
- SbieDLL.dll
- dbghelp.dll
It uses the following credentials when accessing its IRC server:
- USER: "{OS Service Pack}-{3 random numbers} * 0 :{Computer Name}"
- NICK: "{LocaleInfo}|{OS Version}|{OS Service Pack}|{6 random numbers}"
- PASS: ""
SOLUTION
9.750
11.622.02
23 Apr 2015
11.623.00
24 Apr 2015
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
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Scan your computer with your Trend Micro product and note files detected as WORM_SDBOT.MAL
Step 4
Restart in Safe Mode
Step 5
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
- netmanlr
- netmanlr
Step 6
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\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
- EnableFirewall = "0"
- EnableFirewall = "0"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wscsvc
- Start = "4"
- Start = "4"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wuauserv
- Start = "4"
- Start = "4"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess
- Start = "2"
- Start = "2"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Shell Extensions
- systemxstuff = "{Malware path}\{Malware name}.exe"
Step 7
Search and delete these folders
- {Removable drive letter except A and B}:\RECYCLER\S-1-6-21-2434476501-1644491937-600003330-1213
Step 8
Search and delete AUTORUN.INF files created by WORM_SDBOT.MAL that contain these strings
[autorun]
open=RECYCLER\S-1-6-21-2434476501-1644491937-600003330-1213\autorunme.exe
icon=%SystemRoot%\system32\SHELL32.dll,4
action=Open folder to view files
shell\open=Open
shell\open\command=RECYCLER\S-1-6-21-2434476501-1644491937-600003330-1213\autorunme.exe
shell\open\default=1
Step 9
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_SDBOT.MAL. 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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