Twelve Tricks is a

Trojan horse The Trojan Horse was a wooden horse said to have been used by the Greeks during the Trojan War to enter the city of Troy and win the war. The Trojan Horse is not mentioned in Homer's ''Iliad'', with the poem ending before the war is concluded, ...

that first appeared around 1990.

Purdue University Purdue University is a public land-grant research university in West Lafayette, Indiana, and the flagship campus of the Purdue University system. The university was founded in 1869 after Lafayette businessman John Purdue donated land and mone ...

issued a bulletin about the Trojan on March 8, 1990.The Twelve Tricks Trojan Horse
/ref> The Trojan came in an altered utility file called CORETEST.COM, which was intended to test performance of

hard drive A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magne ...

s. It affected IBM platform computers running

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few ope ...

PC DOS PC or pc may refer to: Arts and entertainment * Player character or playable character, a fictional character controlled by a human player, usually in role-playing games or computer games * '' Port Charles'', an American daytime TV soap opera * ...

. The Trojan alters the master boot record (partition sector) and, at every reboot, it installs one of twelve "tricks" that causes issues with hardware or operation of the computer. The trick vanishes when the power is cut off, and any of the twelve tricks may appear or reappear on the next reboot. In addition, on each boot the Trojan uses a random number generator to determine whether to do a low-level format of the active copy of the boot sector and the first copy of the

FAT In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (triple est ...

; there is a 1/4096 chance of this happening. If the format does not happen, the Trojan randomly changes one random word in any of the first sixteen sectors of the FAT, leading to a gradual corruption of the file system.

References

External links

* ''Morality and Machines'
214
Trojan horses {{malware-stub