Multiple Apple iOS Zero-Days Enabled Firm To Spy On Targeted iPhone Users For Years

Apple’s much vaunted reputation for security took a bit of beating this week with two separate reports identifying serious vulnerabilities in its iOS operating system for iPhones and iPads.

One of the reports, from security firm Lookout and the University of Toronto’s Citizen Lab, details a trio of zero-day vulnerabilities in iOS, dubbed Trident, that a shadowy company called the NSO Group has been exploiting for several years to spy on targeted iOS users.

The NSO Group is based in Israel but owned by an American private-equity firm.  The company has developed a highly sophisticated spyware product called Pegasus that takes advantage of the Trident zero-day exploit chain to jailbreak iOS devices and install malware on them for spying on users.

In an alert this week, security researchers at Citizen Lab and Lookout described Pegasus as one of the most sophisticated endpoint malware threats they had ever encountered. The malware exploits a kernel base mapping vulnerability, a kernel memory corruption flaw and a flaw in the Safari WebKit that basically lets an attacker compromise an iOS device by getting the user to click on a single link.

All three are zero-days flaws, which Apple has addressed via its 9.3.5 patch. The researchers are urging iOS users to apply the patch as soon as possible.

Pegasus, according to the security researchers, is highly configurable and is designed to spy on SMS text messages, calls, emails, logs and data from applications like Facebook, Gmail, Skype, WhatsApp and Viber running on iOS devices.

“The kit appears to persist even when the device software is updated and can update itself to easily replace exploits if they become obsolete,” the researchers said in their alert.

Evidence suggests that Pegasus has been used to conduct so-called ‘lawful intercepts’ of iOS owners by governments and government-backed entities. The malware kit has been used to spy on a noted human rights activist in the United Arab Emirates, a Mexican journalist who reported on government corruption and potentially several individuals in Kenya, the security researchers said.

The malware appears to emphasize stealth very heavily and the authors have gone to considerable efforts to ensure that the source remains hidden. “Certain Pegasus features are only enabled when the device is idle and the screen is off, such as ‘environmental sound recording’ (hot mic) and ‘photo taking’,” the researchers noted.  

The spyware also includes a self-destruct mechanism, which can activate automatically when there is a probability that it will be discovered.

Like many attacks involving sophisticated malware, the Pegasus attack sequence starts with a phishing text—in this case a link in an SMS message—which when clicked initiates a sequence of actions leading to device compromise and installation of malware.

Because of the level of sophistication required to find and exploit iOS zero-day vulnerabilities, exploit chains like Trident can fetch a lot of money in the black and gray markets, the researchers from Citizen Lab and Lookout said. As an example they pointed to an exploit chain similar to Trident, which sold for $1 million last year.

The second report describing vulnerabilities in IOS this week came from researchers at the North Carolina State University, TU Darmstadt, a research university in Germany and University Politehnica in Bucharest.

In a paper to be presented at an upcoming security conference in Vienna, the researchers said they focused on iOS’ sandbox feature to see if they could find any security vulnerabilities that could be exploited by third-party applications. The exercise resulted in the researchers unearthing multiple vulnerabilities that would enable adversaries to launch different kinds of attacks on iOS devices via third-party applications.

Among them were attacks that would let someone bypass iOS’ privacy setting for contacts, gain access to a user’s location search history, and prevent access to certain system resources. In an alert, a researcher who co-authored the paper said that the vulnerabilities have been disclosed to Apple, which is now working on fixing them.

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