Some viruses can be all things to all machines. Depending on what needs to be infected, they can infect system sectors or they can infect files. These … [Read more...]

Many viruses take the easy way out when infecting files; they simply attach themselves to the end of the file and then change the start of the program … [Read more...]

One method of virus detection is an interception program which sits in the background looking for specific actions that might signify the presence of … [Read more...]

You don't hear much about this type of virus. Fortunately it is rare and, because of the way anti-virus programs have evolved, is unlikely to occur in … [Read more...]

Some viruses rewrite themselves completely each time they infect. These viruses are said to be metamorphic. As you might expect, the programming … [Read more...]

The NT File System (NTFS) contains within it a system called Alternate Data Streams (ADS). This subsystem allows additional data to be linked to a … [Read more...]

To confound virus scanning programs, virus writers created polymorphic viruses. These viruses are more difficult to detect by scanning because each … [Read more...]

Viruses are sometimes also categorized by how they infect. These categorizations often overlap the categories above and may even be included in the … [Read more...]

While rare, it is possible to infect actual programming source code found on your computer. Source code comes in many forms because of the many … [Read more...]