|Technical name||Avast: Win32:Nimda
Kaspersky: Net-Worm.Win32.Nimda or I-Worm.Nimda
|Point of origin||China (alleged)|
|Operating system(s) affected||Windows 95 – XP|
Nimda is a computer worm, also a file infector. It quickly spread, surpassing the economic damage caused by previous outbreaks such as Code Red. Nimda utilized several types of propagation techniques and this caused it to become the Internet’s most widespread virus/worm within 22 minutes.
The worm was released on September 18, 2001. Due to the release date, exactly one week after the attacks on the World Trade Center and Pentagon, some media quickly began speculating a link between the virus and Al Qaeda, though this theory ended up proving unfounded.
The worm's name origin comes from the reversed spelling of it, which is "admin".
Methods of infection
- Open network shares
- Browsing of compromised web sites
- exploitation of various Microsoft IIS 4.0 / 5.0 directory traversal vulnerabilities. (Both Code Red and Nimda were hugely successful exploiting well known and long solved vulnerabilities in the Microsoft IIS server.)
- Back doors left behind by the "Code Red II" and "sadmind/IIS" worms.
- https://www.cert.org/historical/advisories/CA-2001-26.cfm CERT first released an advisory on the worm on September 18, 2001