Christmas Tree EXEC

Christmas Tree EXEC
Other namesCHRISTMA EXEC, CHRISTMAS EXEC
Original author(s)Unknown Clausthal University of Technology student
Initial releaseDecember 1987
Written inREXX
PlatformIBM System/370
TypeComputer worm, malware, trojan horse

Christmas Tree EXEC was the first widely disruptive computer worm, which paralyzed several international computer networks in December 1987.[1] The virus ran on the IBM VM/CMS operating system.

Written by a student at the Clausthal University of Technology in the REXX scripting language, it drew a crude Christmas tree as text graphics, then sent itself to each entry in the target's email contacts file. In this way it spread onto the European Academic Research Network (EARN), BITNET, and IBM's worldwide VNET. On all of these systems it caused massive disruption.

The core mechanism of the ILOVEYOU worm of 2000 was essentially the same as Christmas Tree, although it ran on PCs rather than mainframes, was spread over a different network, and was scripted using VBScript rather than REXX.

  1. ^ Tom Scott (2015-12-21). "A Christmas Computer Bug, and the Future of Files" (video). YouTube. Archived from the original on 2021-12-21. Retrieved 2017-11-05.