Internet Security Threats

W32.Fujacks.AF is a worm that spreads through network shares. It also copies itself to the root drive of all partitions.

When W32.Fujacks.AF is executed, it copies itself as:
%Windir%\logo_1.exe
[DRIVE LETTER]\pif.exe

It then creates the following file to execute [DRIVE LETTER]\pif.exe:
[DRIVE LETTER]\autorun.inf

The worm creates the following registry entries, so that it runs every time Windows starts:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Run\"logo1_.exe"="C:\WINDOWS\logo_1.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\"logo1_.exe"="C:\WINDOWS\logo_1.exe"

The worm attempts to end the following processes:
FrogAgent.exe
Mcshield.exe
Ravmon.exe
RavmonD.exe
Ravtask.exe
Rundll32.exe
TBMon.exe
TrojDie.kxp
UpdaterUI.exe
VsTskMgr.exe
logo1_.exe
naPrdMgr.exe
ravmon.exe
system32\drivers\spoclsv.exe

The worm attempts to download the following file from the mm.21380.com domain:
txt.txt

Note: At the time of writing, the file was unavailable from the remote location.

The worm scans the compromised computer and infects any .exe files it finds.

Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

• Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
• If a blended threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
• Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services (for example, all Windows-based computers should have the current Service Pack installed.). Additionally, please apply any security updates that are mentioned in this writeup, in trusted Security Bulletins, or on vendor Web sites.
• Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
• Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files.
• Isolate infected computers quickly to prevent further compromising your organization. Perform a forensic analysis and restore the computers using trusted media.
• Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.