<s>
The	O
Java	B-Device
platform	I-Device
provides	O
a	O
number	O
of	O
features	O
designed	O
for	O
improving	O
the	O
security	O
of	O
Java	B-Device
applications	O
.	O
</s>
<s>
This	O
includes	O
enforcing	O
runtime	O
constraints	O
through	O
the	O
use	O
of	O
the	O
Java	B-Language
Virtual	I-Language
Machine	I-Language
(	O
JVM	B-Language
)	O
,	O
a	O
security	O
manager	O
that	O
sandboxes	O
untrusted	O
code	O
from	O
the	O
rest	O
of	O
the	O
operating	B-General_Concept
system	I-General_Concept
,	O
and	O
a	O
suite	O
of	O
security	O
APIs	B-General_Concept
that	O
Java	B-Device
developers	O
can	O
utilise	O
.	O
</s>
<s>
Despite	O
this	O
,	O
criticism	O
has	O
been	O
directed	O
at	O
the	O
programming	O
language	O
,	O
and	O
Oracle	B-Application
,	O
due	O
to	O
an	O
increase	O
in	O
malicious	O
programs	O
that	O
revealed	O
security	O
vulnerabilities	O
in	O
the	O
JVM	B-Language
,	O
which	O
were	O
subsequently	O
not	O
properly	O
addressed	O
by	O
Oracle	B-Application
in	O
a	O
timely	O
manner	O
.	O
</s>
<s>
The	O
binary	O
form	O
of	O
programs	O
running	O
on	O
the	O
Java	B-Device
platform	I-Device
is	O
not	O
native	O
machine	O
code	O
but	O
an	O
intermediate	O
bytecode	B-Language
.	O
</s>
<s>
The	O
JVM	B-Language
performs	O
verification	O
on	O
this	O
bytecode	B-Language
before	O
running	O
it	O
to	O
prevent	O
the	O
program	O
from	O
performing	O
unsafe	O
operations	O
such	O
as	O
branching	O
to	O
incorrect	O
locations	O
,	O
which	O
may	O
contain	O
data	O
rather	O
than	O
instructions	O
.	O
</s>
<s>
It	O
also	O
allows	O
the	O
JVM	B-Language
to	O
enforce	O
runtime	O
constraints	O
such	O
as	O
array	B-Data_Structure
bounds	I-Data_Structure
checking	I-Data_Structure
.	O
</s>
<s>
This	O
means	O
that	O
Java	B-Device
programs	O
are	O
significantly	O
less	O
likely	O
to	O
suffer	O
from	O
memory	B-Application
safety	I-Application
flaws	O
such	O
as	O
buffer	B-General_Concept
overflow	I-General_Concept
than	O
programs	O
written	O
in	O
languages	O
such	O
as	O
C	B-Language
which	O
do	O
not	O
provide	O
such	O
memory	B-Application
safety	I-Application
guarantees	O
.	O
</s>
<s>
It	O
manages	O
memory	O
allocation	O
and	O
initialization	O
and	O
provides	O
automatic	B-General_Concept
garbage	I-General_Concept
collection	I-General_Concept
which	O
in	O
many	O
cases	O
(	O
but	O
not	O
all	O
)	O
relieves	O
the	O
developer	O
from	O
manual	O
memory	O
management	O
.	O
</s>
<s>
This	O
contributes	O
to	O
type	B-Language
safety	I-Language
and	O
memory	B-Application
safety	I-Application
.	O
</s>
<s>
The	O
platform	O
provides	O
a	O
security	O
manager	O
which	O
allows	O
users	O
to	O
run	O
untrusted	O
bytecode	B-Language
in	O
a	O
"	O
sandboxed	O
"	O
environment	O
designed	O
to	O
protect	O
them	O
from	O
malicious	O
or	O
poorly	O
written	O
software	O
by	O
preventing	O
the	O
untrusted	O
code	O
from	O
accessing	O
certain	O
platform	O
features	O
and	O
APIs	B-General_Concept
.	O
</s>
<s>
For	O
example	O
,	O
untrusted	O
code	O
might	O
be	O
prevented	O
from	O
reading	O
or	O
writing	O
files	O
on	O
the	O
local	O
filesystem	O
,	O
running	O
arbitrary	O
commands	O
with	O
the	O
current	O
user	O
's	O
privileges	O
,	O
accessing	O
communication	O
networks	O
,	O
accessing	O
the	O
internal	O
private	O
state	O
of	O
objects	O
using	O
reflection	O
,	O
or	O
causing	O
the	O
JVM	B-Language
to	O
exit	O
.	O
</s>
<s>
The	O
security	O
manager	O
also	O
allows	O
Java	B-Device
programs	O
to	O
be	O
cryptographically	O
signed	O
;	O
users	O
can	O
choose	O
to	O
allow	O
code	O
with	O
a	O
valid	O
digital	O
signature	O
from	O
a	O
trusted	O
entity	O
to	O
run	O
with	O
full	O
privileges	O
in	O
circumstances	O
where	O
it	O
would	O
otherwise	O
be	O
untrusted	O
.	O
</s>
<s>
The	O
Java	B-Library
Class	I-Library
Library	I-Library
provides	O
a	O
number	O
of	O
APIs	B-General_Concept
related	O
to	O
security	O
,	O
such	O
as	O
standard	O
cryptographic	O
algorithms	O
,	O
authentication	O
,	O
and	O
secure	O
communication	O
protocols	O
.	O
</s>
<s>
There	O
are	O
a	O
number	O
of	O
possible	O
sources	O
of	O
security	B-Language
vulnerabilities	I-Language
in	I-Language
Java	I-Language
applications	I-Language
,	O
some	O
of	O
which	O
are	O
common	O
to	O
non-Java	O
applications	O
and	O
some	O
of	O
which	O
are	O
specific	O
to	O
the	O
Java	B-Device
platform	I-Device
.	O
</s>
<s>
Examples	O
of	O
potential	O
sources	O
of	O
vulnerability	O
common	O
to	O
Java	B-Device
and	O
non-Java	O
applications	O
are	O
:	O
</s>
<s>
However	O
,	O
much	O
discussion	O
of	O
Java	B-Language
security	I-Language
focusses	O
on	O
potential	O
sources	O
of	O
vulnerability	O
specific	O
to	O
the	O
Java	B-Device
platform	I-Device
.	O
</s>
<s>
A	O
vulnerability	O
in	O
the	O
Java	B-Device
platform	I-Device
will	O
not	O
necessarily	O
make	O
all	O
Java	B-Device
applications	O
vulnerable	O
.	O
</s>
<s>
When	O
vulnerabilities	O
and	O
patches	O
are	O
announced	O
,	O
for	O
example	O
by	O
Oracle	B-Application
,	O
the	O
announcement	O
will	O
normally	O
contain	O
a	O
breakdown	O
of	O
which	O
types	O
of	O
application	O
are	O
affected	O
(	O
)	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
hypothetical	O
security	O
flaw	O
which	O
affects	O
only	O
the	O
security	O
manager	O
sandboxing	O
mechanism	O
of	O
a	O
particular	O
JVM	B-Language
implementation	O
would	O
mean	O
that	O
only	O
Java	B-Device
applications	O
which	O
run	O
arbitrary	O
untrusted	O
bytecode	B-Language
would	O
be	O
compromised	O
:	O
applications	O
where	O
the	O
user	O
fully	O
trusts	O
and	O
controls	O
all	O
bytecode	B-Language
being	O
executed	O
would	O
not	O
.	O
</s>
<s>
This	O
would	O
mean	O
that	O
,	O
say	O
,	O
a	O
web	B-Application
browser	I-Application
plugin	B-Application
based	O
on	O
that	O
JVM	B-Language
would	O
be	O
vulnerable	O
to	O
malicious	O
applets	O
downloaded	O
from	O
public	O
websites	O
,	O
but	O
a	O
server-side	O
web	O
application	O
running	O
on	O
the	O
same	O
version	O
of	O
the	O
JVM	B-Language
where	O
the	O
administrator	O
has	O
full	O
control	O
over	O
the	O
classpath	B-Language
would	O
be	O
unaffected	O
.	O
</s>
<s>
As	O
with	O
non-Java	O
applications	O
,	O
security	O
vulnerabilities	O
can	O
stem	O
from	O
parts	O
of	O
the	O
platform	O
which	O
may	O
not	O
initially	O
appear	O
to	O
be	O
security-related	O
.	O
</s>
<s>
For	O
example	O
,	O
in	O
2011	O
,	O
Oracle	B-Application
issued	O
a	O
security	O
fix	O
for	O
a	O
bug	O
in	O
the	O
method	O
.	O
</s>
<s>
This	O
method	O
converts	O
a	O
string	O
such	O
as	O
"	O
12.34	O
"	O
into	O
the	O
equivalent	O
double-precision	O
floating	B-Algorithm
point	I-Algorithm
number	I-Algorithm
.	O
</s>
<s>
The	O
security	O
manager	O
in	O
the	O
Java	B-Device
platform	I-Device
(	O
which	O
,	O
as	O
mentioned	O
above	O
,	O
is	O
designed	O
to	O
allow	O
the	O
user	O
to	O
safely	O
run	O
untrusted	O
bytecode	B-Language
)	O
has	O
been	O
criticized	B-Language
in	O
recent	O
years	O
for	O
making	O
users	O
vulnerable	O
to	O
malware	O
,	O
especially	O
in	O
web	B-Application
browser	I-Application
plugins	B-Application
which	O
execute	O
Java	B-Device
applets	O
downloaded	O
from	O
public	O
websites	O
,	O
more	O
informally	O
known	O
as	O
"	O
Java	B-Device
in	O
the	O
browser	B-Application
"	O
.	O
</s>
<s>
Oracle	B-Application
's	O
efforts	O
to	O
address	O
these	O
vulnerabilities	O
resulted	O
in	O
a	O
delay	O
to	O
the	O
release	O
of	O
Java	B-Device
8	B-Application
.	O
</s>
<s>
An	O
OS	B-Operating_System
X	I-Operating_System
trojan	O
referred	O
to	O
as	O
Flashback	B-Application
exploited	O
a	O
vulnerability	O
in	O
Java	B-Device
,	O
which	O
had	O
not	O
been	O
patched	O
by	O
Apple	O
,	O
although	O
Oracle	B-Application
had	O
already	O
released	O
a	O
patch	O
.	O
</s>
<s>
In	O
April	O
,	O
Apple	O
later	B-Operating_System
released	O
a	O
removal	O
tool	O
for	O
Lion	B-Application
users	O
without	O
Java	B-Device
.	O
</s>
<s>
With	O
Java	B-Device
7	B-Application
Update	O
4	O
,	O
Oracle	B-Application
began	O
to	O
release	O
Java	B-Device
directly	O
for	O
Lion	B-Application
and	O
later	B-Operating_System
.	O
</s>
<s>
In	O
October	O
,	O
Apple	O
released	O
an	O
update	O
that	O
removed	O
the	O
Java	B-Device
plugin	B-Application
from	O
all	O
browsers	B-Application
.	O
</s>
<s>
This	O
was	O
seen	O
as	O
a	O
move	O
by	O
Apple	O
to	O
distance	O
OS	B-Operating_System
X	I-Operating_System
from	O
Java	B-Device
.	O
</s>
<s>
In	O
January	O
,	O
a	O
zero-day	O
vulnerability	O
was	O
found	O
in	O
all	O
versions	O
of	O
Java	B-Device
7	B-Application
,	O
including	O
the	O
latest	O
version	O
Java	B-Device
7	B-Application
Update	O
10	O
,	O
which	O
was	O
already	O
exploited	O
in	O
the	O
wild	O
.	O
</s>
<s>
In	O
response	O
,	O
Apple	O
blacklisted	O
the	O
latest	O
version	O
of	O
the	O
Java	B-Device
plugin	B-Application
.	O
</s>
<s>
Oracle	B-Application
released	O
a	O
patch	O
(	O
Update	O
11	O
)	O
within	O
three	O
days	O
.	O
</s>
<s>
Microsoft	O
also	O
released	O
a	O
patch	O
for	O
Internet	B-Application
Explorer	I-Application
versions	B-Application
6	I-Application
,	O
7	B-Application
,	O
and	O
8	B-Application
.	O
</s>
<s>
Cyberespionage	O
malware	O
Red	O
October	O
was	O
found	O
exploiting	O
a	O
Java	B-Device
vulnerability	O
that	O
was	O
patched	O
in	O
October	O
2011	O
.	O
</s>
<s>
The	O
website	O
for	O
Reporters	O
Without	O
Borders	O
was	O
also	O
compromised	O
by	O
a	O
Java	B-Device
vulnerability	O
in	O
versions	O
prior	O
to	O
Update	O
11	O
.	O
</s>
<s>
After	O
the	O
release	O
of	O
Update	O
11	O
,	O
another	O
vulnerability	O
began	O
circulating	O
online	O
,	O
which	O
was	O
later	B-Operating_System
confirmed	O
.	O
</s>
<s>
It	O
was	O
also	O
found	O
that	O
Java	B-Device
's	O
security	O
mode	O
itself	O
was	O
vulnerable	O
due	O
to	O
a	O
bug	O
.	O
</s>
<s>
In	O
response	O
,	O
Mozilla	B-Operating_System
disabled	O
Java	B-Device
(	O
as	O
well	O
as	O
Adobe	B-Application
Reader	I-Application
and	O
Microsoft	B-Application
Silverlight	I-Application
)	O
in	O
Firefox	B-Application
by	O
default	O
,	O
while	O
Apple	O
blacklisted	O
the	O
latest	O
Java	B-Device
plugin	B-Application
again	O
.	O
</s>
<s>
Twitter	O
advised	O
users	O
to	O
disable	O
Java	B-Device
,	O
although	O
it	O
did	O
not	O
explain	O
why	O
.	O
</s>
<s>
Later	B-Operating_System
in	O
the	O
month	O
,	O
Facebook	O
reported	O
that	O
it	O
had	O
been	O
hacked	O
by	O
a	O
zero-day	O
Java	B-Device
attack	O
.	O
</s>
<s>
It	O
was	O
found	O
that	O
a	O
breach	O
of	O
an	O
iPhone	B-Device
developer	O
forum	O
was	O
used	O
to	O
attack	O
Twitter	O
,	O
Facebook	O
,	O
and	O
Apple	O
.	O
</s>
<s>
Another	O
vulnerability	O
discovered	O
allowed	O
for	O
the	O
Java	B-Language
security	I-Language
sandbox	O
to	O
be	O
completely	O
bypassed	O
in	O
the	O
original	O
release	O
of	O
Java	B-Device
7	B-Application
,	O
as	O
well	O
as	O
Updates	O
11	O
and	O
15	O
.	O
</s>
<s>
In	O
March	O
,	O
trojan	O
called	O
McRat	O
was	O
found	O
exploiting	O
a	O
zero-day	O
Java	B-Device
vulnerability	O
.	O
</s>
<s>
Oracle	B-Application
then	O
released	O
another	O
patch	O
to	O
address	O
the	O
vulnerability	O
.	O
</s>
