Welcome to the Virus Encyclopedia of Panda Security.
|Effects: ||It finishes processes, sends out confidential information, launches DoS attacks, and modifies files on IIS servers.|
|First detected on:||June 5, 2003|
|Detection updated on:||June 10, 2003|
|Yes, using TruPrevent Technologies
Lentin.R is a dangerous worm that ends active processes on the affected computer. In addition, it sends out an e-mail message with confidential information to the attacking user.
Lentin.R also launches DoS attacks on five Internet websites.
Finally, Lentin.R checks if the computer under attack is an IIs web server (Internet Information Server). If this is the case, it modifies all files with HTM or HTML extension found in the root directory of the hard drive, by adding two links to the worm author's website.
Lentin.R spreads extremely quickly by e-mail. The e-mail it sends out has variable characteristics. Moreover, if the affected computer is connected to a network, the worm creates three copies of itself in all available shared network drives.
It is very easy to become infected by this worm, as it is automatically activated when the message is viewed through Outlook’s Preview Pane. It does this by exploiting a vulnerability in Internet Explorer (versions 5.01 and 5.5), which allows e-mail attachments to be automatically run. This vulnerability exploit is known as Exploit/iFrame.
Lentin.R is difficult to recognize, as it does not display any messages or warnings that indicate that it has infected a computer.
It is also difficult to identify the messages carrying Lentin.R, as their characteristics vary each time. The name of the attached file that carries out the infection is selected at random from a list and has an SCR, EXE or COM extension.
If you want to see the list of possible names for the file attached to the e-mail message in which Lentin.R reaches the computer, click here.