Apple is reportedly working to fix an SMS message handling vulnerability in its iPhone that could be used by an attacker to run unauthorized code with full access to the device.

According to IDG News Service, Apple has been notified about the vulnerability and is working on a patch that's planned for release prior to the Black Hat USA security conference later this month.

Apple did not immediately respond to a request for comment. But iPhone vulnerabilities are not unheard of: The company's recent iPhone 3.0 software release included 46 fixes for security vulnerabilities.

At Black Hat, which runs from July 25-30 in Las Vegas, Charlie Miller, a security researcher with Independent Security Evaluators, plans to present information about the vulnerability.

Miller mentioned the vulnerability in an iPhone security presentation on Thursday at the SyScan security conference in Singapore, but declined to provide details, citing an agreement with Apple, IDG reports.

Miller was not immediately available to comment.

He plans to participate in two presentations at Black Hat: "Post Exploitation Bliss: Loading Meterpreter on a Factory iPhone" and "Fuzzing the Phone in your Phone."

The former talk will explain how to inject unsigned code into an iPhone's process address space. The latter will explore how to inject SMS messages into iPhones, Android phones, and Windows Mobile devices using a technique called fuzzing.

Both this year and last, Miller has won Apple hardware at the CanSecWest security conference's Pwn2Own contest by exploiting previously unknown vulnerabilities in Apple's Safari Web browser.

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