The Infamous Friday the 13th Virus

The Infamous Friday The 13th Virus: A History Lesson

Jerusalem and its variants have thankfully become obsolete, but now we have much more sophisticated hacks and malware to deal with. If this old virus taught us anything, it is that prevention is key. 

Ah, Friday the 13th. To some, this day just comes and goes like any other; to others, it is almost a virus in itself!

A source of terrible luck and a day that should be feared. Today we learned that fear of Friday the 13th is called paraskevidekatriaphobia – try saying that three times fast!

How Did Friday The 13th Virus Get Its Name?

Whether you believe in the superstitions surrounding the day or not, we thought it would be fun to celebrate by telling you about a computer virus that was famous for executing its dirty work on the unluckiest day of the year, every year.

The Friday the 13th virus is actually called The virus Jerusalem, and was first created in 1987 with one objective in mind. The virus contained one destructive payload that was set to activate on Friday the 13th on all years except 1987.

How The Friday the 13th Virus Worked

  • Activated on Friday the 13th based on the computer clock.
  • Silently infected .EXE and .COM files under MS-DOS.
  • Caused computer systems to slow due to increased memory usage.

The Friday the 13th virus would infect a computer through the use of CD-ROM, floppies, and email attachments and every year.

On Friday the 13th, all the programs and files that were being used would be infected and removed, confirmed by the disassembly below. (Except in 1987)

Friday the 13th virus

How Did Users Avoid The Virus?

Do you remember being warned of this in the late 80s and early 90s?

Apparently some “experts” would suggest changing your system clock so that your computer would actually avoid Friday the 13th and skip right to the 14th.

However, the malware was slowing your system down and reducing your memory every other day of the year, so this method may not have been the most effective.

A New Era of Cyber Protection

This is a prime example of prevention prevailing over reaction – the ability to detect the virus in your system before it was able to infect and delete your files would have been extremely useful.

Unfortunately, back then there may not have been tools that would allow this.

But now? Now we have a product that was developed to detect hacker tradecraft in the first few stages of a breach!

Jerusalem and its variants have thankfully become obsolete due to modern operating systems.

However, now we have much more sophisticated hacks and malware to deal with.

If this old virus taught us anything, it is that prevention is key.

Contact us today to learn how we can help you prepare for when, not if, a breach happens to your company.

Enjoy your Friday as best you can, even if it is Friday the 13th!

BlackPoint Cyber