<s>
Mebroot	B-Application
is	O
a	O
master	B-Device
boot	I-Device
record	I-Device
based	O
rootkit	O
used	O
by	O
botnets	B-Architecture
including	O
Torpig	O
.	O
</s>
<s>
The	O
Trojan	O
infects	O
the	O
MBR	O
to	O
allow	O
itself	O
to	O
start	O
even	O
before	O
the	O
operating	B-General_Concept
system	I-General_Concept
starts	O
.	O
</s>
<s>
This	O
allows	O
it	O
to	O
bypass	O
some	O
safeguards	O
and	O
embed	O
itself	O
deep	O
within	O
the	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
It	O
is	O
known	O
that	O
the	O
Trojan	O
can	O
intercept	O
read/write	O
operations	O
,	O
embed	O
itself	O
deep	O
within	O
network	O
drivers	B-Application
.	O
</s>
<s>
This	O
allows	O
it	O
the	O
ability	O
to	O
bypass	O
some	O
firewalls	B-Application
and	O
communicate	O
securely	O
,	O
using	O
a	O
custom	O
encrypted	O
tunnel	B-Protocol
,	O
to	O
the	O
command	O
and	O
control	O
server	O
.	O
</s>
<s>
Mebroot	B-Application
is	O
linked	O
to	O
Anserin	O
,	O
which	O
is	O
another	O
Trojan	O
that	O
logs	O
keystrokes	O
and	O
steals	O
banking	O
information	O
.	O
</s>
<s>
This	O
gives	O
further	O
evidence	O
showing	O
that	O
financial	O
motive	O
is	O
most	O
likely	O
behind	O
Mebroot	B-Application
.	O
</s>
<s>
Mebroot	B-Application
has	O
no	O
executable	O
files	O
,	O
no	O
registry	B-Protocol
keys	I-Protocol
,	O
and	O
no	O
driver	O
modules	O
,	O
which	O
makes	O
it	O
harder	O
to	O
detect	O
without	O
antivirus	B-Application
software	I-Application
.	O
</s>
<s>
In	O
addition	O
to	O
running	O
antivirus	B-Application
software	I-Application
,	O
one	O
can	O
also	O
remove	O
the	O
Trojan	O
by	O
wiping	O
or	O
repairing	O
the	O
master	B-Device
boot	I-Device
record	I-Device
,	O
the	O
hard	B-Device
drive	I-Device
,	O
and	O
the	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
Three	O
variants	O
of	O
Mebroot	B-Application
have	O
been	O
discovered	O
.	O
</s>
<s>
In	O
December	O
,	O
Mebroot	B-Application
started	O
drive-by	O
downloads	O
.	O
</s>
<s>
Since	O
the	O
third	O
variant	O
,	O
the	O
Trojan	O
has	O
been	O
upgraded	O
to	O
try	O
and	O
outwit	O
antivirus	B-Application
software	I-Application
.	O
</s>
<s>
It	O
is	O
unknown	O
if	O
Mebroot	B-Application
is	O
still	O
in	O
the	O
wild	O
.	O
</s>
<s>
Mebroot	B-Application
is	O
currently	O
known	O
to	O
be	O
distributed	O
by	O
visiting	O
malicious	O
websites	O
,	O
or	O
by	O
way	O
of	O
an	O
application	B-Application
exploit	O
.	O
</s>
<s>
Traffic	O
to	O
websites	O
infected	O
with	O
Mebroot	B-Application
can	O
reach	O
50,000	O
to	O
100,000	O
views	O
per	O
day	O
.	O
</s>
