Security researchers warn of a new class of Apple bugs
Security researchers say they have uncovered a “new class” of vulnerabilities that could allow attackers to bypass Apple’s security protections in iOS and macOS to access users' sensitive data.
Trellix’s Advanced Research Center published details this week of the privilege escalation vulnerabilities — meaning they allow someone to gain an elevated level of access to the system — affecting both iPhones and Macs. Trellix warned that the class of bugs, which range from medium to high severity, could — if left unpatched — allow malicious apps to escape their protective "sandbox" and access sensitive information on someone's device, including a person's messages, location data, call history and photos.
Trellix’s findings follow earlier research from Google and Citizen Lab, which in 2021 discovered a new zero-day exploit dubbed ForcedEntry that was abused by Israeli spyware maker NSO Group to remotely and stealthily hack into iPhones at the behest of its government customers. Apple subsequently strengthened its device security protections by adding in new code-signing mitigations, which cryptographically verify that the device's software is trusted and hasn't been modified, to stop the exploitation of the exploit.
But Trellix said this week that the mitigations put in place by Apple are insufficient to prevent similar attacks.
In a blog post, Trellix said the new bugs involve NSPredicate, a tool that allows developers to filter code, around which Apple tightened restrictions following the ForcedEntry bug through a protocol called NSPredicateVisitor. But Trellix said that nearly every implementation of NSPredicateVisitor "could be bypassed."
While Trellix has seen no evidence to suggest that these vulnerabilities have been actively exploited, the cybersecurity company tells TechCrunch that its research shows that iOS and macOS are "not inherently more secure" than other operating systems.
"The vulnerabilities uncovered by our team this week have fundamentally broken their security model," said Doug McKee, director of Vulnerability Research at Trellix, adding that the bugs could have, in theory, exposed affected Apple devices to a wide range of attack vectors and made it easier for improper access to sensitive data. "These bugs essentially allow an attacker that has achieved low privileged code execution, i.e., basic functions on macOS or iOS, to gain much higher privileges."
Apple patched the vulnerabilities Trellix found in its macOS 13.2 and iOS 16.3 software updates, released in January. Apple’s security support documents were also updated on Tuesday to reflect the release of the new patches.
Will Strafach, a security researcher and founder of the Guardian firewall app, described the vulnerabilities as "pretty clever," but warned that there is little the average user can do about these threats, "besides staying vigilant about installing security updates."
And iOS and macOS security researcher Wojciech Reguła told TechCrunch that while the vulnerabilities could be significant, in the absence of exploits, more details are needed to determine how big this attack surface is.
Jamf's Michael Covington said that Apple's code-signing measures were "never intended to be a silver bullet or a lone solution" for protecting device data. "The vulnerabilities, though noteworthy, show how layered defenses are so critical to maintaining good security posture," Covington said.
When reached, Apple did not provide an on-the-record comment.