Category Archives: Viruses

The common story is that two brothers from Pakistan analyzed the boot sector of a floppy disk and developed a method of infecting it with a virus dubbed “Brain” (the origin is generally accepted but not absolutely). Because it spread widely on the popular MS-DOS PC system this is typically called the first computer virus; even though it was predated by Cohen’s experiments and the Apple II virus. That same year the first PC-based Trojan was released in the form of the popular shareware program PC-Write. Some reports say Virdem was also found this year; it is often called the first file virus.

Basit and Amjaad Farooq Alvi owned a computer store in Pakistan, and wrote the virus to leave their contact information on computers. It soon spread and was relatively harmless although it infected PCs worldwide. The brothers claimed they had done it to study software piracy in Pakistan, ostensibly because they were software vendors. The brothers are still in business today in Pakistan as internet service provider Brain Limited.

The first computer worm, dubbed the “Morris worm” after it’s creator Robert Morris Jr., appeared in the winter of 1988. It was not written to cause damage, but to spread. Morris originally had benign reasons for creating it, claiming it was to gauge the size of the internet. A Cornell University graduate student, he released the worm from MIT on Nov. 2nd, 1988. What he didn’t know is the worm’s code had a bug, and it quickly infected computers by the thousands.

The worm worked by exploiting vulnerabilities in the Unix operating system along with sendmail, fingerd, and other packages. It only infected DEC VAX machines running 4 BSD and Sun 3. It was programmed to reproduce itself and other files, and filter through the networks. The size of the reproduced files eventually filled a computer’s memory due to the unintended bug, effectively disabling them.

Morris was eventually arrested and became the first person tried under the Computer Fraud and Abuse Act of 1986. He was sentenced to three years of probation, 400 hours of community service, and a fine of $10,050. The worm also prompted the creation of the Computer Emergency Response Team (CERT), and has also been called “The Great Worm” because of it’s disastrous effect. Morris was also the son of the chief scientist at the National Computer Security Center, part of the National Security Agency.

In 1982, 15 year old student Richard Skrenta wrote the first known computer virus in the wild. Also known as the Apple II virus, Elk Cloner spread by infecting Apple II systems via infected floppy disks. Although not causing any deliberate harm, it was extremely annoying. On every 50th boot, the virus would display on-screen:

Elk Cloner:  The program with a personality!

It will get on all your disks
It will infiltrate your chips
Yes it’s Cloner!

It will stick to you like glue
It will modify ram too
Send in the Cloner!

It infected floppy disks that were inserted into the victim machine, spreading from disk to disk although it wouldn’t harm the working of the computer itself. Skrenta was apparently a known prankster, and created a way to attack his friend’s disks without having physical access to them. It was a highly contagious virus, infecting the machines of several people he knew. Part of it’s success is attributed to the lack of user awareness, and the fact that at the time there were no such things as anti virus programs. Although it could be removed, it was a difficult manual process.

Even Skrenta’s math teacher was infected with the virus. Wonder if he got a passing grade? He is currently CEO of Topix.net, an online news aggregator.