Research In Motion has released a patch that addresses a potential security vulnerability for enterprise BlackBerry users.

The smartphone maker warned customers last week that malicious PDFs had the potential to compromise devices that use a BlackBerry Enterprise Server. The vulnerability is similar to one that appeared last year for BES, but this one could also infect the computer that runs the BlackBerry Attachment Service.

"Multiple security vulnerabilities exist in the PDF distiller of some released versions of the BlackBerry Attachment Service," RIM said in its warning. "These vulnerabilities could enable a malicious individual to send an e-mail message containing a specifically crafted PDF file, which when opened for viewing on a BlackBerry smartphone, could cause memory corruption and possibly lead to arbitrary code execution on the computer that hosts the BlackBerry Attachment Service."

The vulnerability potentially affects customers with BES 4.1 Service Pack 3 through BES 5.0, and security software to combat this issue can be downloaded from RIM's Web site. The company also has issued a workaround in the interim, and it advises BlackBerry users to only open attachments from trusted sources.

The bug is a slight chink in RIM's armor, as its BlackBerry smartphones are dominant in the enterprise space because of their high level of security. While hackers generally aim their viruses at a company's computers, many security experts believe smartphones will be increasingly targeted as more and more businesses deploy these mobile computing devices. No mobile platform is completely secure, though, as rivals like Symbian have been targeted by Trojans, and security vulnerabilities have been discovered with Apple's iPhone.

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