Malware type: Worm

Aliases: Backdoor.Win32.Wootbot.fk (Kaspersky), W32.Spybot.Worm (Symantec), TR/Crypt.XPACK.Gen (Avira), Mal/EncPk-DM (Sophos),

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 98, ME, NT, 2000, XP, Server 2003

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:


Distribution potential:



A worm is a malware that is designed to propagate and spread across networks. Worms are known to propagate using one or several of different transmission vectors like email, IRC, network shares, instant messengers (IM), and peer-to-peer (P2P) networks.

Worms do not infect files, but may carry one or more payloads, such as computer security compromise and information theft.

Worms typically modify system settings to automatically start. Users may need to terminate worms before they can be deleted. Also, restoring affected systems may require procedures other than scanning with an antivirus program.

For additional information about this threat, see:

Description created: Jan. 6, 2010 12:36:17 AM GMT -0800


File type: PE

Memory resident:  Yes

Size of malware: 77,975 Bytes

Initial samples received on: Jan 6, 2010


Arrival Details

This worm may be dropped by other malware.

It may be downloaded unknowingly by a user when visiting malicious Web site(s).


This worm drops the following copy(ies) of itself:

  • %System%\fixweb.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.)

Autostart Techniques

This worm creates the following registry entry(ies) to enable its automatic execution at every system startup:

Windows has Layer = "fixweb.exe"

Windows has Layer = "fixweb.exe"

It registers itself as a system service to ensure its automatic execution at every system startup. It does this by creating the following registry key(s)/entry(ies):

DisplayName = "Windows has Layer"

ImagePath = "%System%\fixweb.exe -netsvcs"

Start = "4"

Analysis By: Jasper Manuel


Minimum scan engine version needed: 8.900

Pattern file needed: 5.225.00

Pattern release date: Jan 6, 2010

Important note: The "Minimum scan engine" refers to the earliest Trend Micro scan engine version guaranteed to detect this threat. However, Trend Micro strongly recommends that you update to the latest version in order to get comprehensive protection. Download the latest scan engine here.


For Windows ME and XP users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

 Step 1: Identify and terminate files detected as WORM_SPYBOT.AWS  [learn how]


  1. For Windows 98 and ME users, Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. 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.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

 Step 2:  Delete this registry key  [learn how]

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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

    • ffor.mylifez.net

 Step 3:  Delete these registry values  [learn how]

    • Windows has Layer = "fixweb.exe"
    • Windows has Layer = "fixweb.exe"

 Step 4: Scan your computer with your Trend Micro product to delete files detected as WORM_SPYBOT.AWS  

*Note: 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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