How to Recover from Blaster virus [was Re: Updated W32.Blaster.worm Alert]

From: Kent W. England [MVP] (kwe_at_mvps.org)
Date: 08/13/03 

Date: Tue, 12 Aug 2003 23:12:02 -0700

This article wraps everything up quite nicely, including how to remove
the infection without wiping out your system. Good job.

The only thing I would add is that if you can't keep your system up long
enough to read and follow these directions, try killing the msblast.exe
process using Task Manager. This should give you sufficient time. If you
reboot before cleaning, kill it again. 

-- 
Kent W. England, Microsoft MVP for Windows
"Jerry Bryant [MSFT]" <jbryant@online.microsoft.com> wrote in message
news:OpJ0nySYDHA.1620@TK2MSFTNGP12.phx.gbl...
> PSS Security Response Team Alert - New Virus: W32.Blaster.worm Update
>
> SEVERITY: CRITICAL
> DATE: August 12, 2003
> PRODUCTS AFFECTED: Windows XP, Windows 2000, Windows Server 2003,
Windows NT
> 4.0, NT 4.0 Terminal Services Edition
>
> Update: PSS Security has updated the recovery procedures in this
bulletin.
> Windows 9X operating systems are not affected by this virus.
> **********************************************************************
>
> PRODUCTS AFFECTED: Windows XP, Windows 2000, Windows Server 2003,
Windows NT
> 4.0, NT 4.0 Terminal Services Edition
>
> WHAT IS IT?
> The Microsoft Product Support Services Security Team is issuing this
alert
> to inform customers about a new worm named W32.Blaster.Worm which is
> spreading in the wild. This virus is also known as: W32/Lovsan.worm
> (McAfee), WORM_MSBLAST.A (Trendmicro), Win32.Posa.Worm (Computer
> Associates). Best practices, such as applying security patch MS03-026
should
> prevent infection from this worm.
>
> Date discovered: August 11, 2003.  Customers who had previously
applied the
> security patch MS03-026  are protected.  To deterimine if the virus is
> present on your machine see the technical details below.
>
> IMPACT OF ATTACK:
> Spread through open RPC ports. Customer's machine gets re-booted or
the file
> "msblast.exe" exists on customer's system.
>
> TECHNICAL DETAILS:
> This worm scans a random IP range to look for vulnerable systems on
TCP port
> 135. The worm attempts to exploit the DCOM RPC vulnerability patched
by
> MS03-026.
>
> Once the Exploit code is sent to a system, it downloads and executes
the
> file MSBLAST.EXE from a remote system via TFTP. Once run, the worm
creates
> the registry key:
> HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
"windows
> auto update" = msblast.exe I just want to say LOVE YOU SAN!! bill
>
> Symptoms of the virus: Some customers may not notice any symptoms at
all. A
> typical symptom is the system is rebooting every few minutes without
user
> input. Customers may also see:
>
> - Presence of unusual TFTP* files
> - Presence of the file msblast.exe in the WINDOWS SYSTEM32 directory
>
> To detect this virus, search for msblast.exe in the WINDOWS SYSTEM32
> directory or download the latest anti-virus software signature from
your
> anti-virus vendor and scan your machine.
>
> For additional information on recovering from this attack please
contact
> your preferred anti-virus vendor.
>
> RECOVERY:
> Security best practices suggest that previously compromised machines
be
> wiped and rebuilt to eliminate any undiscovered exploits that can lead
to a
> future compromise.  See Cert Advisory:
> Steps for Recovering from a UNIX or NT System Compromise.
> http://www.cert.org/tech_tips/win-UNIX-system_compromise.html
>
> However, many Anti-Virus companies have written tools to remove the
known
> exploit associated with this particular worm.  To download the removal
tool
> from your antivirus vendor follow procedures outlined below.
>
> For Windows XP
> 1. First, enable the built in firewall such as Internet Connection
Firewall
> (ICF) in Windows XP:  http://support.microsoft.com/?id=283673
> --In Control Panel, double-click "Networking and Internet
Connections", and
> then click "Network Connections".
> --Right-click the connection on which you would like to enable ICF,
and then
> click "Properties".
> --On the Advanced tab, click the box to select the option to "Protect
my
> computer or network".
>
> 2. Second, download the MS03-026 security patch from Microsoft:
>
> Windows XP (32 bit)
>
http://download.microsoft.com/download/9/8/b/98bcfad8-afbc-458f-aaee-b7a52a983f01/WindowsXP-KB823980-x86-ENU.exe
>
> Windows XP (64 bit)
>
http://download.microsoft.com/download/a/7/5/a75b3c8f-5df0-451b-b526-cfc7c5c67df5/WindowsXP-KB823980-ia64-ENU.exe
>
> 3. Third, install or update your antivirus signature software
> 4. Then, download the worm removal tool from your antivirus vendor.
>
> For Windows 2000 systems, where Internet Connection Firewall (ICF) is
not
> available, the following steps will help block the affected ports so
that
> the system can be patched. These steps are based on a modified excerpt
from
> the article; HOW TO: Configure TCP/IP Filtering in Windows 2000.
> http://support.microsoft.com/?id=309798
>
> 1. Configure TCP/IP security on Windows 2000:
> --Select "Network and Dial-up Connections" in the control panel.
> --Right-click the interface you use to access the Internet, and then
click
> "Properties".
> --In the "Components checked are used by this connection" box, click
> "Internet Protocol (TCP/IP)", and then click "Properties".
> --In the Internet Protocol (TCP/IP) Properties dialog box, click
"Advanced".
> --Click the "Options" tab.
> --Click "TCP/IP filtering", and then click "Properties".
> --Select the "Enable TCP/IP Filtering (All adapters)" check box.
> --There are three columns with the following labels:
> TCP Ports
> UDP Ports
> IP Protocols
> --In each column, you must select the "Permit Only" option.
> --Click OK.
>
> 2. Download the MS03-026 security patch for Windows 2000 from
Microsoft at:
>
http://download.microsoft.com/download/0/1/f/01fdd40f-efc5-433d-8ad2-b4b9d42049d5/Windows2000-KB823980-x86-ENU.exe
>
> 3. Install or update your antivirus signature software
> 4. Then, download the worm removal tool from your antivirus vendor.
>
> For additional details on this worm from anti-virus software vendors
> participating in the Microsoft Virus Information Alliance (VIA) please
visit
> the following links:
>
> Network Associates:
>
http://us.mcafee.com/virusInfo/default.asp?id=description&virus_k=100547
>
> Trend Micro:
>
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=WORM_MSBLAST.A
>
> Symantec:
>
http://securityresponse.symantec.com/avcenter/venc/data/w32.blaster.worm.html
>
> Computer Associates:
> http://www3.ca.com/virusinfo/virus.aspx?ID=36265
>
> For more information on Microsoft's Virus Information Alliance please
visit
> this link:
> http://www.microsoft.com/technet/security/virus/via.asp
>
> As always, please make sure to use the latest Anti-Virus detection
software
> signature from your Anti-Virus vendor to detect new viruses and their
> variants.
>
> PREVENTION:
> Turn on Internet Connection Firewall (Windows XP or Windows Server
2003) or
> use a third party firewall to block TCP ports 135, 139, 445 and 593;
UDP
> port 135, 137,138; also UDP 69 (TFTP) and TCP 4444 for remote command
shell.
>
> To enable the Internet Connection Firewall in Windows:
> http://support.microsoft.com/?id=283673
>
> -In Control Panel, double-click Networking and Internet Connections,
and
> then click Network Connections.
> -Right-click the connection on which you would like to enable ICF, and
then
> click Properties.
> -On the Advanced tab, click the box to select the option to "Protect
my
> computer or network".
>
> This worm utilizes a previously-announced vulnerability as part of its
> infection method. Because of this, customers must ensure that their
> computers are patched for the vulnerability that is identified in
Microsoft
> Security Bulletin MS03-026.
> http://www.microsoft.com/technet/security/bulletin/MS03-026.asp.
>
> Install the patch MS03-026 from Windows Update:
>
> Windows NT 4 Server & Workstation
>
http://download.microsoft.com/download/6/5/1/651c3333-4892-431f-ae93-bf8718d29e1a/Q823980i.EXE
>
> Windows NT 4 Terminal Server Edition
>
http://download.microsoft.com/download/4/6/c/46c9c414-19ea-4268-a430-53722188d489/Q823980i.EXE
>
> Windows 2000
>
http://download.microsoft.com/download/0/1/f/01fdd40f-efc5-433d-8ad2-b4b9d42049d5/Windows2000-KB823980-x86-ENU.exe
>
> Windows XP (32 bit)
>
http://download.microsoft.com/download/9/8/b/98bcfad8-afbc-458f-aaee-b7a52a983f01/WindowsXP-KB823980-x86-ENU.exe
>
> Windows XP (64 bit)
>
http://download.microsoft.com/download/a/7/5/a75b3c8f-5df0-451b-b526-cfc7c5c67df5/WindowsXP-KB823980-ia64-ENU.exe
>
> Windows 2003 (32 bit)
>
http://download.microsoft.com/download/8/f/2/8f21131d-9df3-4530-802a-2780629390b9/WindowsServer2003-KB823980-x86-ENU.exe
>
> Windows 2003 (64 bit)
>
http://download.microsoft.com/download/4/0/3/403d6631-9430-4ff6-a061-9072a4c50425/WindowsServer2003-KB823980-ia64-ENU.exe
>
> As always, please make sure to use the latest Anti-Virus detection
from your
> Anti-Virus vendor to detect new viruses and their variants.
>
> RELATED MICROSOFT SECURITY BULLETINS:
> http://www.microsoft.com/technet/security/bulletin/MS03-026.asp
>
> RELATED KB ARTICLES: http://support.microsoft.com/?kbid=826955
> This article will be available within 24 hours.
>
> RELATED LINKS:  http://www.microsoft.com/security/incident/blast.asp
>
> If you have any questions regarding this alert please contact your
Technical
> Account Manager or Application Development Consultant.
>
> PSS Security Response Team
> If you have any questions regarding this alert please contact your
Microsoft
> representative or 1-866-727-2338 (1-866-PCSafety) within the US,
outside of
> the US please contact your local Microsoft Subsidiary.  Support for
virus
> related issues can also be obtained from the Microsoft Virus Support
> Newsgroup which can be located by clicking on the following link
> news://msnews.microsoft.com/microsoft.public.security.virus.
>
> PSS Security Response Team
>
>
> -- 
> Regards,
>
> Jerry Bryant - MCSE, MCDBA
> Microsoft IT Communities
>
> Get Secure! www.microsoft.com/security
>
>
> This posting is provided "AS IS" with no warranties, and confers no
rights.
>
>

Relevant Pages
Quantcast