<s>
ScreenOS	B-Operating_System
is	O
a	O
real-time	B-Operating_System
embedded	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
for	O
the	O
NetScreen	O
range	O
of	O
hardware	O
firewall	O
devices	O
from	O
Juniper	O
Networks	O
.	O
</s>
<s>
Beside	O
transport	O
level	O
security	O
ScreenOS	B-Operating_System
also	O
integrates	O
these	O
flow	O
management	O
applications	O
:	O
</s>
<s>
In	O
December	O
2015	O
,	O
Juniper	O
Networks	O
announced	O
that	O
it	O
had	O
found	O
unauthorized	O
code	O
in	O
ScreenOS	B-Operating_System
that	O
had	O
been	O
there	O
since	O
August	O
2012	O
.	O
</s>
<s>
A	O
2011	O
leaked	O
NSA	O
document	O
says	O
that	O
GCHQ	O
had	O
current	O
exploit	O
capability	O
against	O
the	O
following	O
ScreenOS	B-Operating_System
devices	O
:	O
NS5gt	O
,	O
N25	O
,	O
NS50	O
,	O
NS500	O
,	O
NS204	O
,	O
NS208	O
,	O
NS5200	O
,	O
NS5000	O
,	O
SSG5	O
,	O
SSG20	O
,	O
SSG140	O
,	O
ISG	O
1000	O
,	O
ISG	O
2000	O
.	O
</s>
