Welcome to the Virus Encyclopedia of Panda Security.
|Alias:||W32/Nimda.E@mm, I-Worm.Nimda, Nimda.E, PE_NIMDA.E, PE_NIMDA.E-O, NIMDA.E, W32/Nimda.E@mm, W32/Nimda-D, W32.Nimda.E@mm|
|Effects: ||It infects files with an EXE extension in all the computers connected to a network. It allows shared access to the hard drive C: in the infected computer. It launches DoS attacks.|
|First detected on:||June 19, 2002|
|Detection updated on:||March 20, 2006|
|Country of origin:||CHINA|
Nimda.E is a dangerous worm, which is highly contagious and difficult to recognize. It spreads extremely quickly using its own methods, through the following means:
- E-mail messages with an attachment called SAMPLE.EXE. Nimda.E exploits a vulnerability in Internet Explorer (versions 5.01 and 5.5), which allows it to carry out its infection when the message carrying the virus is viewed in the Preview Pane.
- Web pages. Nimda.E uses the Web Directory Traversal Exploit in IIS Web servers to modify pages written in the language HTML. It modifies these pages by inserting a script in them. When users access modified pages, they will be infected.
- Computer networks. It allows shared access to the hard disk C: in the infected computer.
The danger of Nimda.E lies in its capacity to spread and infect, which allows it to significantly increase HTTP traffic, resulting in a Denial of Service (DoS).
Its aim is to spread to as many computers connected to a network as possible and infect all the files with an EXE extension that it finds.
It is difficult to know if you have received the message carrying Nimda.E, regardless of the means of transmission used.
The only clear indication that Nimda.E has reached your computer is a file called SAMPLE.EXE, which is attached to the e-mail messages that are infected with this virus.