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Worm:Win32/Slenfbot.ALJ
Aliases: TR/Jorik.CB (Avira) TROJ_SPNR.19HH12 (Trend Micro) Trojan.Slenfbot!CWAv87o1cjE (VirusBuster) Trojan.Win32.Jorik (Ikarus) Trojan.Win32.Jorik.Slenfbot.axk (Kaspersky) Win32/Slenfbot.AD (ESET)
Summary
This worm spreads automatically via shares, but must be ordered to spread via an exploit or IRC-like commands by a remote attacker. The worm also contains backdoor functionality that allows unauthorized access to an affected computer.
Worm:Win32/Slenfbot.ALJ is a member of the Win32/Slenfbot family of worms.
To detect and remove this threat and other malicious software that may be installed on your computer, run a full-system scan with an appropriate, up-to-date, security solution. The following Microsoft products detect and remove this threat:
- Microsoft Security Essentials or, for Windows 8, Windows Defender
- Microsoft Safety Scanner
- Microsoft Windows Malicious Software Removal Tool
Update vulnerable applications
This threat exploits the vulnerability MS06-040 in Windows 2000, XP and Server 2003. After removing this threat, make sure that you install the updates available from Microsoft. You can read more about the vulnerability, as well as where to download the software update, at Microsoft Security Bulletin MS06-040.
Recovering from recurring infections on a network
The following additional steps may need to be taken to completely remove this threat from an infected network, and to stop infections from recurring from this and other similar types of network-spreading malware:
- Ensure that an antivirus product is installed on ALL computers connected to the network that can access or host shares.
- Ensure that all available network shares are scanned with an up-to-date antivirus product.
- Restrict permissions as appropriate for network shares on your network. For more information on simple access control, please see: http://technet.microsoft.com/library/bb456977.aspx.
- Remove any unnecessary network shares or mapped drives.
Note: Additionally it may be necessary to temporarily change the permission on network shares to read-only until the disinfection process is complete.
Disable Autorun functionality
This threat attempts to spread via removable drives on computers that support Autorun functionality. This is a particularly common method of spreading for many current malware families. For information on disabling Autorun functionality, please see the following article:
http://support.microsoft.com/kb/967715/
Additional remediation instructions for Worm:Win32/Slenfbot.ALJ
This threat may make lasting changes to a computer's configuration that are not restored by detecting and removing this threat. For more information on returning an infected computer to its pre-infected state, please see the following articles:
- Restoring your system registry:
- For Windows 7
- For Windows Vista
- For Windows XP
- Viewing hidden and/or system files:
- For Windows 7
- For Windows Vista
- For Windows XP
- Stopping and starting Windows services:
- For Windows 7
- For Windows Vista
- For Windows XP
- Correctly disabling Autorun in Windows