A team of researchers has conducted an analysis of Apple’s OS X and iOS operating systems and determined that the mechanisms put in place to prevent applications from interacting with each other are not very efficient.
In a paper titled “Unauthorized Cross-App Resource Access on MAC OS X and iOS,” researchers from Indiana University, Peking University, and Georgia Institute of Technology demonstrated that cross-app resource access (XARA) attacks are possible on Apple’s operating systems, allowing malicious applications to steal passwords and other sensitive data from other programs.
Modern operating systems are designed to separate applications to ensure that they are protected against malware and compromised apps. However, researchers have managed to develop an experimental application that allowed them to bypass the restrictions.
“We conducted the first study on the XARA risks of Apple’s isolation mechanisms, and discovered surprising security-critical vulnerabilities: major cross-app resource-sharing mechanisms (such as keychain) and communication channels (including WebSocket and Scheme) turn out to be insufficiently protected by both the OS and the apps using them, allowing a malicious program to steal from these apps sensitive user data,” researchers wrote in their paper. “Also the BID [Bundle ID]-based sandbox construction is found to be less reliable than expected, and its resource-sharing mechanism can be exploited by the malicious app to break the sandbox confinement on OS X, gaining full access to other apps’ directories.”
The proof-of-concept (PoC) application, which the experts managed to upload to the Apple App Store, demonstrated that a malicious app can steal secret tokens and passwords for iCloud, email, and social networks from the Internet Accounts system app, and Gmail and banking credentials from Google Chrome. The application also collected private notes, contacts and the secret token from Evernote, passwords maintained by the password manager 1Password, and photos from WeChat.
Experts have analyzed a total of 1,612 popular OS X apps and 200 iOS apps, and determined that over 86 percent of them are exposed to XARA attacks.
The root cause of these vulnerabilities, according to researchers, is that in most cases the operating systems and the vulnerable applications don’t properly authenticate the party they interact with.
Researchers reported their findings to Apple on October 15, 2014 and communicated again with the company in November 2014 and early 2015. Apple told the experts that given the nature of the problem it needs six months to address the flaws. However, the issues still haven’t been properly fixed.
The researchers have developed an application that detects exploit attempts on OS X in an effort to help protect vulnerable apps until the bugs are properly addressed.
The developers of the impacted applications have been notified of the vulnerabilities. Agilebits, the developer of 1Password, confirmed that malware could capture information sent by the 1Password browser extension and 1Password mini for Mac, and provided users some recommendations on how to protect themselves against potential attacks. However, the company has pointed out that such malware is actually less dangerous that a malicious browser extension.
