A new variant of MyDoom worm - Mydoom.X, was found on September 10th, 2004. This worm variant is similar to the previous variants: Mydoom.U-W. It spreads in emails with different subject and body texts, downloads and activates a backdoor.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.
The worm is a PE executable file 18432 bytes long packed with UPX file compressor. The unpacked file's size is over 44 kilobytes.
When run, the worm creates a mutex 'LLLf54fxrDLLL', copies itself as WIN32S.EXE to Windows System Directory and creates a startup key for that file in System Registry:
where "%WinSysDir%" represents Windows System directory.
Additionally, the worm copies itself to the 'Start Menu\Programs\Startup\' folder of a current user as AUTORUN.EXE file.
The worm spreads by sending its infected attachment to all email addresses found on an infected computer. The worm looks for email addresses in Windows Address Book (WAB) and in the files with the following extensions:
The worm avoids sending emails to email addresses that contain any of the following substrings:
The subject of infected emails is selected from the following variants:
The body text of infected emails is selected from the following variants:
-----Original Message----- From: Jeny K. Sent: Tuesday, September 7, 2004 8:57 PM To: Morpheus check my new photos :)) miss you, jeny k -----Original Message----- From: Jena K. Sent: Tuesday, September 7, 2004 5:23 AM To: friends Check Out Archive.. So.. What Do You Think... Am I Hot? :) Waining For Your Answer Jena Key -----Original Message----- From: jenny k. Sent: Tuesday, September 7, 2004 10:23 AM To: My Tiger (email) new fotos(archived) you asked jenny k -----Original Message----- From: jenna k. (email) Sent: Tuesday, September 7, 2004 11:38 AM To: Cat my new fotos archived )) kiss, jenna k -----Original Message----- From: Jeny Sent: Tuesday, September 7, 2004 8:57 PM To: Neo see the photos in attached archive :)) kiss you, jeny -----Original Message----- From: Jena Sent: Tuesday, September 7, 2004 5:23 AM To: friend Photos in archive.. So.. Am I Hot? :) Waining For Your Answer Jena -----Original Message----- From: Jenna Knukles Sent: Tuesday, September 7, 2004 9:05 AM To: Friends Group in self-extracting archive my photos Jenna :) -----Original Message----- From: jenna (email) Sent: Tuesday, September 7, 2004 11:38 AM To: ma kittie my photos archived )) kiss, jenna -----Original Message----- From: Jeny K. Sent: Tuesday, September 7, 2004 8:57 PM To: Morpheus check out the new photos :)) miss you, jeny k -----Original Message----- From: Jena K. Sent: Tuesday, September 7, 2004 5:23 AM To: friends So.. What Do You Think... Am I Hot? :) Waining For Your Answer Jena Key -----Original Message----- From: Jenna Knukles Sent: Tuesday, September 7, 2004 9:05 AM in archive my new fotos Jenna K :) -----Original Message----- From: jenny k. Sent: Tuesday, September 7, 2004 10:23 AM To: My Tiger (email) new fotos you asked jenny k -----Original Message----- From: jenna k. (email) Sent: Tuesday, September 7, 2004 11:38 AM To: Cat my new fotos zipped )) kiss, jenna k -----Original Message----- From: Jeny Sent: Tuesday, September 7, 2004 8:57 PM To: Neo see the photos :)) kiss you, jeny -----Original Message----- From: Jena Sent: Tuesday, September 7, 2004 5:23 AM To: friend So.. Am I Hot? :) Waining For Your Answer Jena -----Original Message----- From: Jenna Knukles Sent: Tuesday, September 7, 2004 9:05 AM To: Friends Group in archive my photos Jenna :) -----Original Message----- From: jenny Sent: Tuesday, September 7, 2004 10:23 AM To: Mr.X (email) photos you asked jenny -----Original Message----- From: jenna (email) Sent: Tuesday, September 7, 2004 11:38 AM To: ma kittie my photos zipped )) kiss, jenna
The worm can send itself as an executable attachment or in a ZIP archive with one of the following names:
Also the worm can attach a fake virus scan report to its message:
where it can be any of the following:
The worm fakes the sender's address. It uses the following list of first names to compose the fake address:
It uses the following list of last names to compose the fake address:
It uses the following list of domain names to compose these fake addresses:
The worm downloads a backdoor from one of websites and activates it. The backdoor is known as 'Surila.J' and is downloaded from the following websites:
After September 17th, 2004, 01:18:31 the worm stops working and deletes its file from a hard drive.