Analysis by: Sabrina Lei Sioting


Backdoor:Win32/Poebot.L (Microsoft), Packed.Win32.PolyCrypt.b (Kaspersky), W32.Linkbot (Symantec), W32/Poebot.gen (McAfee), W32/Poebot.BB (Authentium), Backdoor.Win32.Nepoe (Ikarus), Win32/Poebot trojan (Eset), W32/RXBot.AB.worm (Panda),


Windows 2000, Windows XP, Windows Server 2003


  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes


Infection Channel: Downloaded from the Internet, Dropped by other malware

This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It runs certain commands that it receives remotely from a malicious user. Doing this puts the affected computer and information found on the computer at greater risk.


File Size: 60,928 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 22 Jul 2007
Payload: Steals information

Arrival Details

This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.


This worm drops the following copies of itself into the affected system:

  • %System%\{random}.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • 1af5a9c70e678bd5439397b8a27f6334586e

Autostart Technique

This worm adds the following registry entries to enable its automatic execution at every system startup:

{random value} = "%System%\{random}.exe"


This worm searches the network for the following shared networks onto which it attempts to drop copies of itself:

  • print$
  • C$\Documents and Settings\All Users\Documents\$
  • c$\windows\system32
  • c$\shared
  • c$\winnt\system32
  • admin$
  • Admin$\system32
  • c$\windows
  • c$\winnt
  • e$\shared
  • d$\shared

It uses the following user name and password to gain access to password-protected shares:

  • User name:
    • access
    • admin
    • administrador
    • administrat
    • administrateur
    • administrator
    • admins
    • backup
    • brian
    • chris
    • cisco
    • compaq
    • computer
    • control
    • database
    • domain
    • george
    • guest
    • homeuser
    • internet
    • intranet
    • katie
    • linux
    • oemuser
    • office
    • oracle
    • owner
    • peter
    • server
    • siemens
    • staff
    • student
    • susan
    • teacher
    • technical
    • wwwadmin
  • Password:
    • 12345
    • 123456
    • 1234567
    • 12345678
    • 123456789
    • 1234567890
    • accounting
    • accounts
    • bitch
    • blank
    • changeme
    • databasepass
    • databasepassword
    • db1234
    • dbpass
    • dbpassword
    • deadline
    • default
    • domainpass
    • domainpassword
    • exchange
    • hello
    • letmein
    • login
    • loginpass
    • money
    • nokia
    • oeminstall
    • orainstall
    • outlook
    • pass1234
    • passwd
    • password
    • password1
    • payday
    • qwerty
    • secret
    • sqlpassoainstall
    • temp123
    • win2000
    • win2k
    • win98
    • windows
    • winnt
    • winpass
    • winxp

Backdoor Routine

This worm joins any of the following IRC channel(s):

  • #rxbot_paradise

It executes the following command(s) from a remote malicious user:

  • Create and delete files
  • Download file from the Internet
  • Download an updated version of the malware
  • Execute files remotely
  • Execute FTP functions


This backdoor gets the name of its dropped copy based on the .EXE files found in the Windows system folder. The value name in the autostart registry it creates is also based on the application name of the file name obtained for its dropped copy.

It steals CD keys, serial numbers, user names and/or passwords used in the following:

  • FlashFXP
  • MSN Explorer
  • OutlookExpress
  • World Of Warcraft
  • Unreal3


Minimum Scan Engine: 9.200
VSAPI OPR PATTERN File: 4.609.00
VSAPI OPR PATTERN Date: 22 Jul 2007

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

Identify and terminate files detected as WORM_POEBOT.BO

[ Learn More ]
  1. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  2. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

Delete the registry entry with an unknown data value

[ Learn More ]

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\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • {random value} = "%System%\{random}.exe"

Step 4

Scan your computer with your Trend Micro product to delete files detected as WORM_POEBOT.BO. 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.

Did this description help? Tell us how we did.

Related Malware