Some PDA devices function as a cellular phone, pager, or even a laptop replacement, which provides more connectivity and power, but puts users at an increased risk for virus infection. Three bits of malicious code in particular have targeted Palm devices: the Liberty Crack Trojan horse and the Phage and Vapor viruses. This article will explore existing mechanisms for virus transmittal over PDAs and look at three different antivirus products available for the PDA.

Spreading PDA viruses
There are four common methods of transmission by which a virus could infect a PDA:

  • Through infected e-mail when using a PDA over a wired or wireless Internet connection
  • When syncing with an infected PC
  • Via an infected file transferred from another PDA via infrared (IR)
  • By downloading infected files from the Internet

If you support a corporate network, you likely have a corporate antivirus solution already in place. But what if your users check e-mail on their PDA? Do you have a virus scanner running on your mail server? What will you do if your users want to check an external e-mail account? How will you prevent viruses from infecting their PDA and then passing to your network?

If you have a good antivirus product running on your corporate network, you should be able to avoid most of the viruses released from infecting computers on your network. But even then, the occasional virus is bound to sneak through. If that virus is written to infect the synchronization software used on certain handhelds, a virus could be transmitted to PDAs. Once the virus is resident in the PDA, it can infect others via infected e-mail or file transfers of infected data.

To keep your network and your users’ PDAs as secure as possible, you’ll need to be prepared for any type of virus transfer. Here are a few of the antivirus products available for handhelds.

PDA virus scanners
Trend Micro offers PC-cillin for Wireless, which supports Palm, EPOC, and Pocket PC users. PC-cillin offers protection from all four methods of virus transmission that I listed above and can be downloaded for free from the Trend Micro site. PC-cillin works on the Palm OS 3.1 or higher, Psion Revo or Revo Plus, or Windows CE 3.0. Setup and pattern file updates are accomplished via the PDA synchronization software. Users can scan any file they receive immediately with this fully resident virus scanner or launch PC-cillin and scan their entire device.

McAfee provides VirusScan for Palm, Symbian/EPOC, Pocket PC and Windows CE. Its retail price is $24.95 for one year. It will protect handhelds from viruses received by any of the four methods above as well as viruses that target handheld operating systems directly. For Palm devices, McAfee has released a beta version of Anti-Virus Resident Scanner (MARS) for Palm. This product protects against the three well-known Palm viruses and Trojans (Liberty Crack, Vapor, and Phage). Users can scan for viruses on their device at any time. MARS will also accept new virus pattern signatures as new viruses are released. MARS requires a Palm III or higher with an OS version of 3.0-3.5.

Symantec has released Antivirus 2002 for Palm OS, which retails for $39.95 for one year. On the Palm device, you’ll need Palm OS version 3 or 4 along with a comparable version of HotSync Manager. It also requires 2 MB of RAM and 50K of available device space. On the desktop side, Antivirus 2002 for Palm OS supports Windows 98, Me, 2000, or XP. Virus definition updates are downloaded when the user’s PC connects to the Internet and are transmitted to the Palm device during synchronization.

Planning is key
As PDAs become more popular and functional, they will surely become the target of an increasing number of new viruses. IT departments that support PDAs must integrate PDA virus protection into their overall antivirus strategy. Doing so now will prevent last minute scrambles to restore important PDA information lost to such attacks.

You be the judge

Do you have experience with any of the products mentioned in this article? If so how effective was it? Are there other products that you prefer? Post a comment to this article and tell us what you think.