Name :	Warezov.DC
Size:	Varies
Category:	Malware
Type:	Email-Worm
Platform:	W32

Warezov.DC is a mass-mailing worm that sends itself as e-mail attachments to addresses found on infected computers. It attempts to download updated variants from specified website(s) on the Internet.

It installs itself so that it runs when Windows is started.

Automatic Disinfection

Usually standalone malware (backdoors, worms, trojans, etc.) is automatically removed by F-Secure Anti-Virus (FSAV) starting from version 5.40. Malware files get automatically renamed by FSAV, so they can not be started any more. In some rare cases, when automatic disinfection is not possible, a user can select disinfection action by him/herself to make FSAV rename or delete an infected file. In some special cases it is recommended to use specific disinfection tools provided by F-Secure. They can be downloaded from our ftp site:

ftp://ftp.f-secure.com/anti-virus/tools/

F-Secure Anti-Virus can be purchased from our webshop or from our authorised distributors. A trial version F-Secure Anti-Virus, limited to 30 days, can be downloaded from our website:

http://www.f-secure.com/download-purchase/

All the latest versions of FSAV can download anti-virus database updates automatically. However, these updates can be also downloaded and installed manually from our web or ftp sites:

http://www.f-secure.com/download-purchase/updates.shtml


Manual Disinfection

To manually disinfect standalone malware (backdoors, worms, trojans, etc.) it's usually enough to delete all infected files from a computer and to restart it. Active malware files are usually locked by operating system so different disinfection approaches are required for different operating systems.
Please note that manual disinfection is a risky process, so it is recommended only for advanced users.

If Windows 95, 98 and ME operating system is used, it is recommended to restart a computer from a bootable system diskette and to delete an infected file from command prompt. For example if a malicious file named ABC.EXE is located in Windows folder, it is usually enough to type the following command at command prompt:

DEL C:\WINDOWS\ABC.EXE

and to press Enter. After that an infected file will be gone. If Windows NT, 2000 or XP is used, a malicious file has to be renamed with a different extension (for example .VIR) and then a system has to be restarted. After restart a renamed malicious file will no longer be active and it can be easily deleted manually.


Malware Disinfection Tools

F-Secure provides disinfection tools for certain malware. These tools can be downloaded from this webpage:

http://www.f-secure.com/download-purchase/tools.shtml

ftp://ftp.f-secure.com/anti-virus/tools/


Windows System Restore Issues

If Windows ME or XP is used, it is recommended to disable System Restore feature of these operating systems to prevent a computer from re-infection by an already removed malware. The fact is that System Restore feature of these operating systems might save an infected file into the special folder and copy it back to a hard drive it every time it's been renamed or deleted by F-Secure Anti-Virus or by a user. Instructions on how to disable System Restore feature are here:

Windows ME:
http://www.f-secure.com/v-descs/sfc_dis.shtml

Windows XP:
http://www.f-secure.com/v-descs/sfc_dis1.shtml

It is recommended to re-enable System Restore after disinfection in order to restore stable system configuration in the future, if any crash or incompatibility issue occurs.


Failed Disinfection

In some cases F-Secure Anti-Virus might not disinfect a system automatically. In this case please visit our Support pages:

http://support.f-secure.com/enu/home/virusproblem/howtoclean/

Once Warezov.DC runs, it launches the notepad application and opens a tmp file with encrypted strings as a decoy:



To ensure its execution every system startup, Warezov.DC creates the following launch points in Windows Registry:



The worm drops the following files to a system during its installation phase:



It may also harvest e-mail addresses from the infected system by scanning through files with the following extension names:



The worm filters found e-mail addresses to avoid sending itself to addresses that contain any of the following substrings:



The worm then sends itself as an attachment to the gathered e-mail addresses using the following e-mail format:

TO:


FROM:
The from field may use any of the following format:


Note: %FirstName% may use any of the following:


%SecondName% may use any of the following:


%domain name% may use any of the following:


Examples:


SUBJECT:
The subject may use any of the following strings:


MESSAGE BODY:
It may use any of the following messages:


ATTACHMENT:
The attachment is the donwloader component of the worm. It then downloads the actual worm from the Internet. It may use the following filename format:


%filename% may use any of the following strings:


%ext1% may use any of the following extension names:


%ext2% may use any of the following extension names:


%random%


Example:



The filename is designed to disguise the executable nature of the attachment from the recipient. This worm also uses a text file icon in its attempt to fool recipients into thinking that this file is just a normal text or log file. This is especially true when the - Hide extensions for known file types - option in Windows is enabled.


Terminates several processes mostly anti-virus and security related:



Warezov.DC worm connects to the following websites in order to download more Warezov files:



Additionally, the worm contacts the vedasetionkderun.com website to notify the worm's author. The notification is done with the POST request and it may include some additional data like the worm's version, type and so on.