Since the very earliest days of computer viruses, malware authors have been inspired by the Christmas holidays when developing attacks.
Here’s a quick, and probably incomplete, history of some of the Christmas-related malware that we have seen over the years.
“Christmas Tree” (also known as “CHRISTMA EXEC”), which spread in December 1987, was an early example of an email-aware worm.
Using the subject line
“Let this exec run and enjoy yourself!”
the worm would display EBCDIC character art of a Christmas tree and forward itself via email to other users if activated.
The worm was blamed on a German student, who claimed he just wanted to send greetings to his friends.
In 1990, the Christmas Tree worm resurfaced, forcing IBM to shut down its 350,000 network of terminals.
Read more in my article on the Naked Security website.