Apple botches iPhone patching, says researcher
- — 17 July, 2008 09:45
Apple took more than three months to patch an iPhone vulnerability, even though it had technical details of the bug and had crafted a fix for Mac OS X, the researcher who reported the flaw said Tuesday.
"They messed up," said Charlie Miller, a principal analyst at Independent Security Evaluators (ISE), a Baltimore-based security consultancy, and a noted iPhone and Mac OS X researcher. "For three months I was walking around with a vulnerable iPhone. They had the vulnerability and the exploit, they understood the exploit because they patched it on Mac OS X, but then they said that they didn't know that [the iPhone] was vulnerable."
The WebKit vulnerability, which Apple patched last Friday as part of the iPhone 2.0 update, was reported to the Cupertino, Calif. company in late March after Miller used it to hack a MacBook Air notebook on March 27 during the "PWN to OWN" contest held at the CanSecWest security conference.
Miller traded the vulnerability and his exploit to TippingPoint's Zero Day Initiative (ZDI), the security company's bug bounty program and the contest's sponsor, in exchange for a $10,000 check; TippingPoint immediately reported the vulnerability to Apple. Three weeks later, Apple patched the bug in Safari for Mac OS X by updating the browser to version 3.1.1.
After CanSecWest, Apple asked Miller through ZDI if the bug was also present in the iPhone's version of Safari. He told Apple that he suspected it was, but couldn't confirm, not having had a chance to try out his exploit on the device. "I was in Canada at the time," he said, "and I didn't want to rack up roaming charges on my iPhone. The ZDI people didn't think the iPhone was vulnerable, but I wasn't sure."
Miller gave it little thought after that, assuming that Apple -- which had been given technical details of the vulnerability and the source code of his exploit -- would try the exploit against Safari on the iPhone.
But two weeks ago, after he expressed concern in a story in the Washington Post that Apple hadn't updated the iPhone to fix the vulnerability he'd uncovered, or others that had been patched on Mac OS X since February, Apple sent him an e-mail. "They got all mad, and sent me a nasty e-mail," Miller said. "They said I should have reported this to Apple security rather than to the Washington Post . I told them'I gave you the exploit, what else do you want me to do?'"
In fact, Apple initially said that the vulnerability wasn't serious in the iPhone and iPod touch versions of Safari, and tried to convince Miller that the bug was a different flaw than the one he reported in March.
"What my exploit does is sets up a bunch of stuff, then fills memory with shell code," said Miller. "There's really only one line that does the bad thing. When you run it on the iPhone, and [the exploit] tries to fill up memory, it runs out of memory and then stops [before the line].
"So Apple said that'we ran the exploit and it ran out of memory and it didn't do anything bad'," Miller said. What Apple had apparently not done, he added, was to run the actual exploit line.
Miller knocked Apple's thoroughness. "Obviously, they didn't do a very good job of testing," he said. "They had the source code, and they thought that the iPhone wasn't vulnerable."
The incident made Miller question whether Apple can effectively manage security on its multiple platforms. "I don't think they do a very good job of that," he said when asked his take on Apple's ability to keep Mac OS X and its mobile devices in sync. "They hadn't patched iPhone since February. For more than four months it's had vulnerabilities that they patched in Mac OS X."
Five of the 13 iPhone vulnerabilities patched last week had been addressed by Apple in updates to Mac OS X or Safari between March and June.
"Not every single Safari bug will also be on the iPhone, but almost every WebKit bug will," said Miller. "If they're going to patch Mac OS X, I don't see why they can't patch the iPhone at the same time."
Like another security professional, Andrew Storms of nCircle Inc., who criticized Apple yesterday for not matching its talk of iPhone security with timely patches, Miller had a problem with the company's claims. "It's one thing not to patch something, companies do that all the time," he said. "But to advertise that it's been up to date since February, that's a little deceptive."