Phage is a virus on PalmOS. It ends up destroying all executables on the device, rendering it unusable until it is completely restored. Other malware for the PalmOS has been reported, but this is still the only virus on the PalmOS.


Phage can arrive on a Palm PDA when an infected file is beamed to it, installed via HotSync or transferred through a flash memory card.

When executed, the infected application makes the screen go grey, during which time it is actually infecting other files. The virus prepends its code to all Palm executables, which are destroyed in the process. Infected files may shrink to around half their size. Phage does not destroy database files, and all applications can be restored from backup.


The virus is named after a disease that affected an alien race in the series Star Trek: Voyager, Phage was. It is also a real virus that infects bacteria, and is believed to have medical uses. It was even approved as a food additive, by the American Food and Drug Administration. Phage is also the name of a reportedly viral program coded by artist Mary Flanagan.

Antivirus Aliases


Jarno Niemela, Mikko Hypponen., "F-Secure Virus Descriptions: Phage". 2000.09

Motoaki Yamamura., "Palm.Phage.Dropper".

Trend Micro Antivirus, PALM_PHAGE.A.

Tony Smith. The Register, First Palm virus isolated. 2000.09.25

Lucy Sheriff. -, FDA approves viruses as 'food additive'. 2006.08.21