When you buy a firewall you're expecting it to provide some kind of protection, not to give people the keys to your network.
But this is exactly what Juniper pulled off. 'Somebody' put a backdoor in their ScreenOS software in 2012. ScreenOS was acquired by Juniper when it took over competitor Netscreen in 2004.
At this moment there are no indications JunOS is affected. JunOS is another operating system Juniper uses in its devices.
Read the official statement here.
The backdoor is built into two distinct functionalities: the VPN implementation and the SSH and Telnet daemons.
Juniper has new updates for ScreenOS. If you are a customer I would really check this out.