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In the wild:
Medium to high
Low to medium
Methods of propagation:
• Peer to Peer
• Kaspersky: Email-Worm.Win32.Mydoom.au
• Grisoft: I-Worm/Mytob.JE
• VirusBuster: I-Worm.Mytob.EK1
• Eset: Win32/Mydoom.BH
Platforms / OS:
• Windows 98
• Windows 98 SE
• Windows NT
• Windows ME
• Windows 2000
• Windows XP
• Drops a malicious file
• Uses its own Email engine
• Registry modification
Right after execution the following information is displayed:
It copies itself to the following location:
The following file is created:
\systemcall.dll Further investigation pointed out that this file is malware, too. Detected as: Worm/Mydoom.BT.DLL
The following registry key is added in order to run the process after reboot:
The following registry key is added:
It contains an integrated SMTP engine in order to send emails. A direct connection with the destination server will be established. The characteristics are described in the following:
The sender address is spoofed.
Generated addresses. Please do not assume that it was the sender's intention to send this email to you. He might not know about his infection or might not even be infected at all. Furthermore it is possible that you will receive bounced emails telling you that you are infected. This might also not be the case.
– Email addresses found in specific files on the system.
– Email addresses gathered from WAB (Windows Address Book)
– Generated addresses
One of the following:
• Server Report
• Mail Transaction Failed
• Mail Delivery System
The body of the email is one of the lines:
• Mail transaction failed. Partial message is available.
• The message contains Unicode characters and has been sent as a binary attachment.
• The message cannot be represented in 7-bit ASCII encoding and has been sent as a binary attachment.
The filename of the attachment is constructed out of the following:
– It starts with one of the following:
The file extension is one of the following:
The attachment is a copy of the malware itself.
The attachment is an archive containing a copy of the malware itself.
The email looks like the following:
It searches the following files for email addresses:
Address generation for TO and FROM fields:
To generate addresses it uses the following strings:
• sandra; linda; julie; jimmy; jerry; helen; debby; claudia; brenda;
anna; brent; adam; ted; fred; jack; bill; stan; smith; steve; matt;
dave; dan; joe; jane; bob; robert; peter; tom; ray; mary; serg; brian;
jim; maria; leo; jose; andrew; sam; george; david; kevin; mike; james;
michael; alex; john
It combines this with domains from the following list or from addresses found in files on the system
The domain is one of the following:
It does not send emails to addresses containing one of the following strings:
• accoun; certific; listserv; ntivi; support; icrosoft; admin; page;
the.bat; gold-certs; feste; submit; not; help; service; privacy;
somebody; soft; contact; site; rating; bugs; you; your; someone;
anyone; nothing; nobody; noone; webmaster; postmaster; samples; info;
root; mozilla; utgers.ed; tanford.e; pgp; acketst; secur; isc.o;
isi.e; ripe.; arin.; sendmail; rfc-ed; ietf; iana; usenet; fido;
linux; kernel; google; ibm.com; fsf.; gnu; mit.e; bsd; math; unix;
berkeley; foo.; .mil; gov.; .gov; ruslis; nodomai; mydomai; example;
inpris; borlan; sopho; panda; icrosof; syma; avp; .edu; -._!; -._!@;
Prepend MX strings:
In order to get the IP address of the mail server it has the ability to prepend the following strings to the domain name:
In order to infect other systems in the Peer to Peer network community the following action is performed:
– It retrieves the shared folder by querying the following registry key:
If successful, the following files are created:
These files are copies of the malware itself.
The following port is opened:
%malware execution directory%
on TCP port 3127 in order to provide a Socks 4 proxy server.
Right after it becomes active, it starts a DoS attack against the following destination:
The malware program was written in MS Visual C++.
In order to aggravate detection and reduce size of the file it is packed with the following runtime packer:
Description inserted by Irina Boldea on Monday, October 23, 2006
Description updated by Irina Boldea on Monday, November 6, 2006