Experts at Juniper have discovered that an update for its Juniper SRX firewalls opens a root-level account on the network device. The problem affects any system upgraded from Junos OS prior to 12.1X46-D65. When the system upgrade fails, the system goes into a safe mode designed to allow a sysadmin to access it and solve the problem. The issue is tracked as CVE-2016-1278. No other Juniper Networks products or platforms are affected.”]
Source: http://securityaffairs.co/wordpress/55252/hacking/juniper-srx.html