Apple Misstep Leaves iPhones Open to Jailbreak

In a somewhat uncharacteristic blunder, Apple has left iPhones running iOS 12.4, the latest version of its mobile operating system, open to a security bug that the company previously had fixed.

One security researcher has quickly taken advantage of the opportunity to develop and publicly release an exploit for jail-breaking iPhones running iOS 12.4.

This is believed to be the first time in several years that a jailbreak for the most updated version of iOS has become publicly available before a patch for it has been released. Typically, such unpatched Apple exploits can fetch hundreds of thousands of dollars and sometimes, even millions of dollars in dark markets.

Jailbreaking gives iPhone users a way to get past Apple's restrictions and install unapproved applications and services on their devices or to change settings that they normally wouldn't be able to change.

Some security researchers are concerned that attackers could use the unpatched exploit to try and launch attacks on iPhone users via tainted apps, remote exploits, and other methods. Others believe such concerns are overblown.

Apple did not respond immediately to a request seeking comment on the issue or on what the company is doing to address it. But some believe it will issue an update quickly, considering the risks to iPhone users.

News of the latest issue somewhat ironically comes just days after Apple announced a major bug bounty program with big incentives for researchers who find bugs in some of the company's products.

"Apple has historically been very expedient in patching vulnerabilities, so I would expect to see an update pretty soon," says Terence Jackson, chief information security officer at Thycotic. "But until then, iPhone users should exercise a little extra discretion when downloading applications and opening links in email, iMessages, or a browser.”

According to Motherboard, the first to report on the issue, security researchers recently discovered that in developing iOS 12.4 Apple had inadvertently reopened a remote code execution bug (CVE-2019-8605) that the company had patched in the previous iOS 12.3 version.  Google Project Zero researcher Ned Williamson reported that issue to Google earlier this year. Apple had described the bug as a "use after free issue [that] was addressed with improved memory management."

Apple's iOS 12.4 among other things contained a fix for another critical vulnerability that allowed attackers to gain access to iPhones via a malicious iMessage.

Muted Risk

Aaron Zander, head of IT at HackerOne, says that the new jailbreak is a "very cool thing" considering how unusual they have become. However, since the vulnerability and the exploit are now public, the associated risks are more manageable. "This is way different than Apple being completely unaware of the vulnerability and allowing exploits to run wild," Zander says.

The bigger issue is how frequently such missteps happen, he says. Typically, companies develop their major software versions separately from their minor releases - for instance, an X.4 version versus an X.4.1 release. In merging minor and major releases, sometimes changes get missed. "This unfortunately happens all the time, which demonstrates why retesting is so important," Zander notes.

Chris Morales, head of security analytics at Vectra, says some people are likely more excited that they can jailbreak their iPhone while still having the latest version of iOS, and aren't worried about the security risks. "The risk here is that a malicious app can get into the Apple store and exploit a vulnerability. While feasible, it is most likely not a regular occurrence or any more of a risk than already existed," Morales says.

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