Analyst: Jailbroken iPhones more secure than normal ones

Catch 22 for the security conscious.

Apple’s latest version of iOS 4.3.3 shipped with a PDF vulnerability that can only be patched in jailbroken iPhones.

The catch, for security conscious iPhone users, is that the best way to protect the device at present is to jailbreak the device and apply a patch, currently unavailable from Apple.

“Until Apple makes a patch for the latest iOS PDF vulnerability, jailbroken iPhones (with PDF Patcher 2) are more secure than normal ones...,” F-Secure’s chief researcher Mikko Hypponen declared on Twitter Wednesday.

Using the tools provided by, which exploits an iOS PDF flaw, made it “child’s play” to jailbreak an iPhone, Sophos security consultant, Graham Cluley said.

“Usually jailbreaking requires users to connect their device to a computer before they can start to tamper with the set-up of their iPhone or iPad. Sites like JailBreakMe make the process much simpler,” he wrote on the company’s blog.

Websense security researcher Patrick Runald pointed out that “if a PDF can be used to jailbreak your  device, a similar PDF can be used to infect it with malware.”

Sophos' Cluley agreed. “Just imagine how someone with more nefarious intentions could also abuse the vulnerability to install malicious code on your iPad or iPhone.”

“If they exploited the same vulnerability in a copy-cat manoeuvre, cybercriminals could create booby-trapped webpages that could - if visited by an unsuspecting iPhone, iPod Touch or iPad owner - run code on visiting devices.”

As it stands, the only way to protect against such an attack, is to go to the site, jailbreak the iPhone and apply the patch that was provided Comex, the author of the tool, who made the fix for the more "security conscious".

“Until Apple releases an update, jailbreaking will ironically be the best way to remain secure,” Comex wrote.

But if this jailbreak played out the same way as the last one supplied by, users should be safe, F-Secure's Hypponen told

"Nobody used the vulnerability for malicious attacks until Apple patched it.With any luck, this will happen again. That's what we're hoping for."

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Tags Applesophosf-secureGraham CluleyjailbreakPatrick Runaldsecurity newsjailbreakme.comiOS PDF vulnerabilityMikko Hypponen

More about AppleApple.F-SecureSophosWebsense

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