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Virus:W32/Codbot.A.1
Date discovered:15/02/2005
Type:Worm
In the wild:Yes
Reported Infections:Low
Distribution Potential:Medium
Damage Potential:Medium
Static file:Yes
File size:50.176 Bytes
MD5 checksum:6f6affa5a078d9c2b6a3633db7462745
VDF version:6.29.00.125

 General Method of propagation:
   • Local network


Aliases:
   •  Symantec: W32.Codbot.A
   •  Mcafee: W32/Sdbot.worm.gen
   •  Kaspersky: Backdoor.Win32.Codbot.ab
   •  TrendMicro: WORM_CODBOT.B
   •  Sophos: Exp/MS04011-A
   •  Grisoft: BackDoor.Small.7.AT
   •  VirusBuster: Worm.Codbot.A
   •  Eset: Win32/Codbot.E
   •  Bitdefender: Worm.Sdbot.CNY


Platforms / OS:
   • Windows 95
   • Windows 98
   • Windows 98 SE
   • Windows NT
   • Windows ME
   • Windows 2000
   • Windows XP
   • Windows 2003


Side effects:
   • Registry modification
   • Makes use of software vulnerability
   • Third party control

 Files It copies itself to the following location:
   • %SYSDIR%\upnp.exe

 Registry The following registry keys are added in order to load the service after reboot:

– HKLM\SYSTEM\CurrentControlSet\Services\UPnP Configuration
   • "Type"=dword:00000110
   • "Start"=dword:00000002
   • "ErrorControl"=dword:00000000
   • "ImagePath"="%SYSDIR%\upnp.exe"
   • "DisplayName"="Universal Plug and Play Device Configuration"
   • "ObjectName"="LocalSystem"
   • "FailureActions"=%hex values%
   • "Description"="Handling all UPnP related system operations."

 Network Infection In order to ensure its propagation the malware attemps to connect to other machines as described below.

It drops copies of itself to the following network shares:
   • C$\windows\system32
   • c$\winnt\system32
   • ADMIN$\system32\
   • ADMIN$
   • print$


It uses the following login information in order to gain access to the remote machine:

– A list of usernames and passwords:
   • Rendszergazda
   • Beheerder
   • amministratore
   • hallintovirkailijat
   • Administrat
   • Administrateur
   • administrador
   • Administrador
   • administrator
   • Administrator
   • ADMINISTRATOR
   • Password
   • password



Exploit:
It makes use of the following Exploits:
– MS01-059 (Unchecked Buffer in Universal Plug and Play)
– MS02-061 (Elevation of Privilege in SQL Server Web)
– MS03-007 (Unchecked Buffer in Windows Component)
– MS03-026 (Buffer Overrun in RPC Interface)
– MS04-007 (ASN.1 Vulnerability)
– MS04-011 (LSASS Vulnerability)


Remote execution:
–It attempts to schedule a remote execution of the malware, on the newly infected machine. Therefore it uses the NetScheduleJobAdd function.

 IRC To deliver system information and to provide remote control it connects to the following IRC Servers:

Server: 0x41.cyber**********
Port: 6556
Channel: #0x90
Nickname: %nine-digit random character string%
Password: 3nt3r

Server: dev.lsa**********
Port: 6556
Channel: #0x90
Nickname: %nine-digit random character string%
Password: 3nt3r

Server: dev.lsa**********
Port: 6556
Channel: #0x90
Nickname: %nine-digit random character string%
Password: 3nt3r

Server: dev.mem**********
Port: 6556
Channel: #0x90
Nickname: %nine-digit random character string%
Password: 3nt3r



– This malware has the ability to collect and send information such as:
    • CPU speed
    • Current user
    • Free disk space
    • Free memory
    • Malware uptime
    • Information about the network
    • Information about running processes
    • Size of memory
    • Username
    • Information about the Windows operating system


– Furthermore it has the ability to perform actions such as:
    • Disable network shares
    • Download file
    • Enable network shares
    • Kill process
    • Perform network scan
    • Start keylog
    • Start spreading routine
    • Terminate malware
    • Terminate process
    • Updates itself

 Backdoor The following port is opened:

%SYSDIR%\upnp.exe on TCP port 21 in order to provide an FTP server.

 Miscellaneous Mutex:
It creates the following Mutex:
   • 0x0_UPnP_0x0

 File details Programming language:
The malware program was written in MS Visual C++.


Runtime packer:
In order to aggravate detection and reduce size of the file it is packed with a runtime packer.

Description inserted by Irina Boldea on Tuesday, May 16, 2006
Description updated by Irina Boldea on Tuesday, May 16, 2006

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