W98.Universe.Worm was written by the virus writer Benny/29A. This worm has similarities to the Hybris worm written by Vecna. W98.Universe.Worm is not known to be in the wild, and appears to contain a few small bugs, as well as conceptual issues that makes it less likely to operate correctly.
W98.Universe.Worm arrives as an email attachment named Uniclean.zip. The file is not a .zip archive, but is rather an .exe file.
Windows 95 and Windows 98 will not execute files with .zip extensions, even if they are actually program files. However, Windows NT/2000 can execute a program file with a .zip extension from the command prompt, but not from the Windows UI. The worm's code indicates that it was written to operate on Windows 98 platforms.
The email message is as follows:
Dear user
F-Secure, Symantec and Microsoft, top leaders in IT technologies have discovered one very dangerous Internet worm called I-Worm.Universe in the wild. Author of this viral program is well known hacker from Europe under "Benny" nickname from 29A virus writting group. Universe is fast-spreading worm that already destroyed computer systems in FBI and Microsoft. It is heavilly encrypted and very complex. It consists from many independed parts called "modules", which are very variable - every second hour is producted one new module, that completelly changes behaviour of worm, including anti-detection tricks. You should check your system by our anti-virus attached to this mail. All reports please send to our mail address: universe@microsoft.com and/or universe@f-secure.com
Have a nice day,
F-Secure, Symantec and Microsoft, top leaders in IT technologies.
This message is not distributed by F-Secure, Symantec or Microsoft.
If the virus code runs (which is fairly unlikely), the worm installs itself to the \Windows\System folder as Msvbvm60.exe. (It attempts to hide itself because the legitimate file, Msvbvm60.dll might be installed on the system.)
Next, it tries to create a entry in the following registry key:
\Software\Microsoft\Windows\CurrentVersion\Run
After this, W98.Universe.Worm attempts to download a text file from a Web site.
This file lists the available plug-in modules. The worm will download the modules one by one, and install them as Msvbvm60x.dll (where x is a, b, c, and so on). Next, it will execute each plugin module.
The actual plugins are encrypted by RSA, so the worm first needs to decrypt the plugins before installation.
The running worm copy will be registered as a Service Process in order to hide the executable from the Windows 98 task list.
The worm sleeps for a short time and then repeats the downloading process. Because of this, it may install a new functioning module from time to time.
The worm was released with 5 different plugins. They are as follows:
Mail plugin
Attempts to send messages to email addresses that are picked up from HTML files in the Internet Cache directory. After doing so, the worm attempts to use an SMTP server to propagate itself.
Feedback
A message regarding newly infected computers is sent to the virus writer atbenny_29a@hushmail.com. The report contains the date and time of the infections, as well as the name of the computers.
Payload
The worm downloads the Universe.jpg file from the virus writers Web site, and registers it as a wallpaper option. The wallpaper appears as the following:
This plug-in also changes the default page of Internet Explorer to
Mirc
The worm tries to send itself using MIRC by installing a new Script.ini file if Mirc32.exe is installed.
RAR
The worm also has a plugin to support RAR archive infections.
The executables are scrambled with a shareware utility.
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.
If you believe you have been infected, please download the latest virus definitions via LiveUpdate or from the Symantec Security Response Web site.
Click here for instructions on using LiveUpdate to retrieve virus definitions.
Click here to manually download and install virus definitions from the Symantec Security Response Web site.
