macOS Vulnerability Leaks Safari Data

A vulnerability in the latest macOS release could allow a malicious application to access restricted Safari data, an application developer has discovered. 

Apple last year aimed to boost the privacy protections in macOS with the addition of new features in 10.14 Mojave, but Mac applications developer Jeff Johnson says that the platform actually fails to protect users better than before.

The issue, he says, is that macOS Mojave is restricting access to certain folders to only a few applications, but that this protection can be bypassed without the application having to acquire permissions from the user or the system. 

The issue impacts all version of Mojave, including macOS Mojave 10.14.3 Supplemental Update released on February 7, he says. 

One of the folders with restricted access is ~/Library/Safari. Only a few apps have access to the folder, such as Finder, and users can’t even list the content of that folder using the Terminal, Johnson reveals. 

Despite that, the developer was able to bypass these protection without triggering a permission dialog, with the “hardened runtime” enabled. 

“Thus, an app with the ability to spy on Safari could be ‘notarized’ by Apple (as long as it passed their automated malware checks, which I suspect would be no problem). My bypass does not work with sandboxed apps, as far as I can tell,” he says. 

Any application able to bypass the protection and peek inside said folder could examine the user’s web browsing history, thus breaking their privacy. 

While the developer mentions ~/Library/Safari as the impacted restricted folder, the issue could potentially impact other folders as well. 

However, Johnson isn’t the only one to have discovered a way to bypass macOS Mojave restrictions. In fact, as security data scientist Bob Rudis noted in a tweet last week, it might be rather trivial to get past the new security feature. 

Johnson says he reported the vulnerability to Apple last week, and that he already received an automated acknowledgement of the submitted report. 

“Mojave privacy protection is a new feature in macOS 10.14. Any weakness in the privacy protection is simply a flaw in the new feature. You’re as safe on Mojave as you were on High Sierra, which did not have this feature at all. You just might not be safer on Mojave than you were on High Sierra,” he notes. 

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