PalmOS/Phage is the first real virus for the Palm OS PDA operating system.
It works by overwriting the beginning of Palm executables. The host
files are destroyed in the process. Once one infected PRC file is
transferred to Palm, the virus keeps spreading to other Palm
programs until they are all infected (and destroyed).
Picture of what is believed to be the original infector application of Phage virus
This very simple virus does nothing else than replicate itself.
It contains following texts:
FindVictim
PhageMain
You can spot the infection from the fact that when you start an
infected file, the screen goes blank for a second and the program
exits without doing anything visible. During this time the virus
locates and infects all other programs in the system.
Screenshot of Phage infected file starting.
Phage can spread from one Palm to another if infected files are
shared via beaming or installed via a docking station.
Phage has not been found in the wild and can not be considered a
serious threat at this time.
When activated Phage infects and destroys all application files in the
device but does not harm database files. Applications can be restored
by deleting all infected applications and restore the application files
from backups. Or if no backups are available restoring all .prc files from
application distribution packages.
By default the Palm desktop hotsync does not backup application files during
hotsync. So for the future it is recommended that users look for backup software
that enables backing up of the application files during sync. One good place
to look is http://www.palmgear.com
[Analysis: Jarno Niemela & Mikko Hypponen, F-Secure, September 2000]