Soon after the release of HyperCard in 1987, computer viruses appeared that targeted the application.[1] The viruses were written in the HyperTalk programming language and typically spread by infecting the Home stack and then infecting other stacks from there.[2][3]
List of viruses
Name of Virus
Year discovered
Notes
Dukakis
1988
First known HyperCard virus.[1][4] Self-destructs after displaying a message encouraging people to vote for Michael Dukakis.[1][3]
Intended to simply propagate, but because of an error, the virus sometimes copies parts of other stack scripts along with its own code causing stacks to behave unexpectedly. Variants include Merry2Xmas, Lopez, and Crudshot.[3]
HC 9507
1995
Causes the word "Pickle" to be typed at the cursor insertion point. May also cause the computer to crash.[3][6]
Antibody
1997
Eradicates the MerryXmas virus and installs MerryXmas inoculation code into infected stacks.[3]
Independance Day
1997
After July 4, 1997, unsuccessfully attempts to delete random lines of code from stacks.[3]
Blink
1998
After January 1, 1999, causes infected stacks to blink.[3]
Wormcode
2000
Originally posted to the usenet group "comp.sys.mac.hypercard" in a stack called "Font Preview". Aside from spreading, the virus does no damage.[3]