<s>
Devnull	B-Application
is	O
the	O
name	O
of	O
a	O
computer	O
worm	O
for	O
the	O
Linux	B-Application
operating	I-Application
system	I-Application
that	O
has	O
been	O
named	O
after	O
,	O
Unix	B-Application
's	O
null	B-Operating_System
device	I-Operating_System
.	O
</s>
<s>
This	O
worm	O
,	O
once	O
the	O
host	O
has	O
been	O
compromised	O
,	O
downloads	O
and	O
executes	O
a	O
shell	B-Language
script	I-Language
from	O
a	O
web	O
server	O
.	O
</s>
<s>
This	O
downloaded	O
file	O
appears	O
to	O
be	O
an	O
IRC	B-Protocol
client	O
.	O
</s>
<s>
Then	O
the	O
worm	O
checks	O
for	O
presence	O
of	O
the	O
GCC	B-Application
compiler	I-Application
on	O
the	O
local	O
system	O
and	O
,	O
if	O
found	O
,	O
creates	O
a	O
directory	O
called	O
.	O
</s>
<s>
After	O
decompressing	O
,	O
two	O
files	O
are	O
created	O
:	O
an	O
ELF	O
binary	O
file	O
called	O
and	O
a	O
source	O
script	B-Language
file	I-Language
called	O
.	O
</s>
<s>
The	O
executable	O
will	O
scan	O
for	O
vulnerable	O
hosts	O
and	O
use	O
the	O
compiled	O
program	O
to	O
exploit	O
a	O
known	O
OpenSSL	B-Language
vulnerability	O
.	O
</s>
