Security researcher Bruce Schneier has flagged a 404Media report that a cyber-weapons arms manufacturer is exploiting a vulnerability in iOS to bypass Apple's automatic reboot security feature. That feature is designed to put an iPhone into a more secure state if it has not been used for 72 hours.
According to Schneier's summary, the exploit specifically targets that automatic reboot mechanism. The details are limited, and Schneier frames the issue as a possible vulnerability rather than a confirmed one. No independent sources were available to compare against the report.
The significance is that a maker of cyber-weapons may have found a way around a security control meant to protect idle or seized devices. Until Apple or other researchers verify the claim, the practical impact remains uncertain.