Đề Án : Mạng máy nh, Internet, Virus
VIRUS
VIRUS
virus máy tính !"#$
%#$&'()*++,-./0$12
3$4#.56#789:::%:
;.+/<=4,#>2(4?
@0AB(C3$=='(
D)=EF3 &#G#$@8?:::H.&IJ3
K:
L&;+M.DI-GIJ
-2)4B)./K#.5&$2M;+
G#N"2D.)0*4O !%<
H=>2+,H$=P3#
2:
Q+CRST4*2G#$"$G4 !G
$U VW'0/<G$$ !NC+
;:XD !BU VCH>2;$
E'#$G$:QY3,PU V3
/0>D4/PG$ZF%C3
'C+G$YD !U VHK
2MG$/P(Y#FNG3#[Y
'':
Các loại Virus máy tính thường gặp:
L+/)4(,.'*2M$3[E2/)3
C=4+?#),3,-G2I
4E:C+DYD/)WM;.3
2M\#$(]^XN0?3,5E
D/N?($E[.>2$N0&(3,^:
Virus Boot
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Z$#)#.$&6#7A/0jiU %6#7/0ji
oF7#%6#7( 5ji_V7_%/=jipi67:j
#$CB&)*++,/8A6#7
Bpi67:QE3,$Hq=4$$h#M
#$2M$q#M#-GE2 !0/;
D#H2#H2#)&4:Q3,,DG Jj
4G#),r3-=#H2#)3
/P=CM N:
L$C-+#)jYM*^GB^$M
DI !+&:a3=s#$ G^t3N0
j^^u##j^s$a[FN03
$DM/+E320#$D$r9;GN
03Y[/K G7:L+/)D J+
Yv,b3#$((/)C Js$3[E2/)#)/@
h#;&/N,EwFNGFNG*#.:
2/)3 !DGB((DCs
$/)Ds^t3N0j^(aW G&
*FF#$%:
_7x
Đề Án : Mạng máy nh, Internet, Virus
Con ngựa Thành Tơ-roa - Trojan Horse
>&$ -$=,3#$=+&yZ)2$
$'z:$'z#$=$(C4.yZ)2D3,
=>2$:LyZ)2*9=+0E#3,#)$
'z=-h8#r:g-$$C
F4&.#w/!-FD$+$w/C
:
_'22CY#$${2 !:;
{#$=)*'(HOÀN TOÀN KHÔNG CÓ TÍNH CHẤT LÂY LAN:
eMCO+{/P$3#w42' !'(B

#$KWBB<&KWB=./Ns$3„
'&7#$3= €>.•H€N2 d•, !
h><6#7|:j=4I d= B=
7#=2B).,)2M= B7#0):e
$E27#0)3O€>•'$> 5/K"#w:L&G
$ 5$/)D/+:\;$$'-C&
).U3,3#.#C$M7N24.:e
3#b0)WI$+rr$j7##$Z7Z77#)3,
#.#;$!GC$M:QCB3U^g.
c77^( G&^/I^w$
C^$.^c77:
\;-#.#$=#;>UO+$C
AH/Gv)0AKJ=$$r
#)w).$G%ND$=KW$3:L$
EI3,7aX0#C).212B.
BE>2$B).$#$B?rC3
=/N222:
L$GU*<=,/r0#.#
)O$277277#.#89fga K!
_7l
Đề Án : Mạng máy nh, Internet, Virus
"?%H/G#$#h82M,
#.#:Q2MN#$G$$ K!C3%#D}
&#h…#h8#h$/=G$D20#E$Y3, 5
$2G:=#h82M2GD#.3[
FNG30A#h8$,#.5#C
wF=.M$B$$D/+:w
$U[+2!^/I^C)c77;?
'-:
Rootkit

#);.$)C[; d
/)F#b:
Lược sử của virus
Q3,#KBG:‡.WCN""
$&,N$3E3,,+'
#)
• LA`R‚RŠL7`RSxz`Rl‹%2,0#b+-
./0B='(:
• \$4>2C`R‰SM>2C`R‹S*FNGCfF
``SŒ='(#$^_7 u#^-33,4;2M
B>2-$:ZE33G:
• LA`RŒ`QMCFNGG$Bu22#7
cc:
• LA`RŒx)e)yLQ#i)ysk7 Q7#MM
G27K9$:
• LA`RŒ‰\^7a^._Q%MC
))_/<a$u{ :Q'($P2M<
=/7%B= 9x‰S/$3[#.5N08 9
:e.#$#)^7#^MC:
• QY`nA$Xpg2#$
^\X7^:L330A-12*B($G2-$
7F7/#76#7%$2)\ut…\jg:
_7‹
Đề Án : Mạng máy nh, Internet, Virus
• LA`RŒ‹\MCND$ :#$^Z7^:
• LA`RŒŒ\Š7#7NDr#))$D
4$$?g`x:e.#$#))=7rrB
4/8>$$#)J=,%:
• ``JA†/7jnn8+V+?
Bu†_uLo#$#G0‰:SSS:j/K2)JxA$`S:SSS

Đề Án : Mạng máy nh, Internet, Virus
• LAnSSn0Bj7#X Z:g/KFnSJ:
• LAnSSx\g#7=#)V#;>4W#!
0‹l$`S2E:
• LAnSS‚e N=+G;B#$Vg7:\;$(
DM20<|BG$WM<##$B
3F.>2$:QY#$g7D$$B)$W
#$B<C>'$D3#$-<=<#):
0BV$Y#>2=W#!")7%8+ON
W;`Œ8g7Še?:>(I@8C$‹
AnSSlCIe?W2)$xAJ7$xS#=D
:
• \;0AB7$3,F.>2/P/O
*$$BG$$h<B2M
N#$'(Grw3#@"2'74
+)G:X 3G(r42[
$3':Qji*+)2M28/+Y#$
=).:y*20C?&$2$N2M
P+>B2MY2$+GB
3 K!772%P0DG3NDB:
L 9C;2M3$G I*r(;
E$07b9B-$W3#b+:e.Y#$'
=$0FN#)2M/0G3N !m:
• '#DF3#[[+C/;3/r
,)q32#27ND/P?
,%$I+2;B)B2MG22V7%:
er33,ND$G$?DN
+"$=G$=N2BU V
G:\$3#[[D>#$DM%82'?
ND# !,+BY'(:

30A,KDK$(•+ !:
• a7Z$&/K/"3$,/<D
{:::
eH/G,#$/72'/$w7DMˆ>
#>2(:L3/;wnSfgX<#C7:y>0B
3,#)D@N$0:L+#C+;=G4#;33
,40= G2:
L3Bg7<g/7#J;=20?BD/0>X7i77
Z/*(=/7)CV7/3C#$j727:
! I#GH3, ! Gr/,3,8
7bWG K@N=$ND:
_7`S
Đề Án : Mạng máy nh, Internet, Virus
7X7i77Z// j727,*#.5'`G_Q
C$M:>(,I*3#C#)&3$/^$7^
$,D_Q/K5B/KK#b
/0/0>BU V$&( G)Ch_Q:
L&D!)/$, 5 JC322M#$A4_Q/K
5/2GM.: !Š7Š7u7n`
8jˆ</Q#i/KCl‹J(*>$= 
G2^7^#/N -$/7,‚SS:SSS^$C^$
x,//K/"<y$ZJA;#$.^M*^
,'`lG_Q•
jH J*3#>,/"&=2),$  5 $3&
D!2)C#D3C;>2$Y7((
II:
• 7#7Z$2M#)h2mB J:L33,&
G(r4#hG4$D J
,AN#$GB.CA2I:Q2M,$N&
!$#>22$(/z !N2=2'G,#N>

^H^yey)C2M3Cg/\CB -C?%:yey
d#$G/(^0^,?yey(N$3
, 5 $N3:
j"#$ˆ>$D 5-G$ J 5>(#$>G
4$#$8&6#7NK:yG#)C$W;<
)b<M;H3,-G2'?N
D$:
• _M4†V7%Z$#)2M !=G4
>*,*3 &#G==.$I=(;D
2!#):
• Q>a %=G4>#$=2'
22B!?- JDH,&
>2wF;=4"D/K2G/<G
D:Q>3,3(?='($
H !ap67H>g…aj~$H=
9/Ns4$G9QX)Bg'C=
)U V%H3,#$=84;='(222z3
#$3|;{:
Danh sách các đuôi tệp có khả năng di truyền và bị lây nhiễm
Q>2CG$U VD<=30A/K
ND:
• :/jiak#7G2F#7#D%
• :Q277 yjZy7#2k#7G2$#G ; )1yjZ%
• : Q 6#7iU VLG2-BU VL%
_7`n
Đề Án : Mạng máy nh, Internet, Virus
• :Q 6#72%G2-%
• :2#Q#_7#7F7G2BQ#_7#%
• : jiU G2B'(jiU %
• :7F7oF7/#7k#7G2-%

4:
*#.5$).3,-( K
WGq3$3-=$#)#%
&KW(N:L+B.B>/K5
$D/K2G+2!,#.5$#)+2!(
+KW$+27:Q(>4#23,A7N2
4.+="$$G/K#.5
3,#$C#G'C$+;=N":
$2M0#bG+2;2M G3
,"2!$=-./0$#),2+KW
 /)B).(B.2,(
?-2/PrKW>2;3:
Phương thực lây nhiễm qua thư điển tử bao gồm:
 Lây nhiễm vào các file đính kèm7G7 #%:3
 J[D/K5;6#7|/K5
) H ,$^(^/<C
N2 d7F,0/2M;DJO%
 Lây nhiễm do mở một liên kết trong thư điện tửQ#C+G
3, d+=V7/$q$
#h8B( G$G$:j=#C+ d;G
-=)*$/K3,/K#.5:
_7`‚
Đề Án : Mạng máy nh, Internet, Virus
 Lây nhiễm ngay khi mở để xem thư điện tửQ$DJ,
/<M)6#7H<#C+*3,/K#.
5:Q$Y#hBG$:
 Virus lây nhiễm qua mạng Internet
7-2,=*Bc77C+;$G(?
#.5c77<$2'?B$
:

Một số virus có khả năng vô hiệu hoá hoặc can thiệp vào hệ điều hành
làm tê liệt (một số) phần mềm diệt virus. Sau hành động này chúng mới
tiến hành lây nhiễm và tiếp tục phát tán. Một số khác lây nhiễm chính
vào phần mềm diệt virus (tuy khó khăn hơn) hoặc ngăn cản sự cập nhật
của các phần mềm diệt virus. Kể cả cài lại HĐH và cài anti sau đó nhưng
đã quá trễ.
Các cách thức này không quá khó nếu như chúng nắm rõ được cơ chế
hoạt động của các phần mềm diệt virus và được lây nhiễm hoặc phát tác
trước khi hệ thống khởi động các phần mềm này. Chúng cũng có thể sửa
đổi file host của hệ điều hành Windows để người sử dụng không thể truy
cập vào các website và phần mềm diệt virus không thể liên lạc với server
của mình để cập nhật.
Cách phòng chống virus và ngăn chặn tác hại của nó
Q3=.3PĐể không bị lây nhiễm virus thì ngắt kết nối
khỏi mạng, không sử dụng ổ mềm, ổ USB hoặc copy bất kỳ file nào
vào máy tính:LCE($3OE$G
-A<4#$AC+;N#;:
D,vK""/0G$`SST;
,)$2M,=E3,)+
+43,$3/G22/0G &#GB(:
 Sử dụng phần mềm diệt virus
a0G/P/KC=2M G30A>
/+#)$#C!>2> &#G,2M3
#D>/+;:
zCKG3N2M G:
;\GL%aQjQ:
QB;$u27u\~ogo:
\$2$/<jijig7o7#:
 Sử dụng tường lửa
#k7V##%D20=(3FHW $

ji%HU Vf2 7W>2>C
U V%:Q4N*H+=.N2&%-
=uf2 7%BU V:A$Wh
4;/0U V$ji>NPE
222:
 Vận dụng kinh nghiệm sử dụng máy tính
Q J !N02M$2'?C
d30A/K#.5$2M=)/<d
;>2>K24;2M G:L
!M !G,?A? !q3G
_7`‹
Đề Án : Mạng máy nh, Internet, Virus
$$G,/0GG$$ &#G
B(:j=4G0
• Phát hiện sự hoạt động khác thường của máy tínhe2M
!D337$H•/@2MH
FC#$G$8z39#$=- !8Kz[
>/+-8B:\ !'0L>
N-)=>)2B>N+4$
D#BG$HB*?/
DD/@-212>2$H-)
=B#%:j-)=$+D
20 2M?.(M-FNGB:L
3M,/P>2> &#G;N2M
 GH !=2M G,1$
G4:
• ,? !)=,-)=B
2MG4Dj7H2MB
*?/v)_7\7V7%,/+=2C#$G/(
G4)2? !$E+#/=;

 Tạo các dữ liệu phục hồi cho toàn hệ thốngD w#)Gq
3BG$ !g7†77BU Vj7t_:::%$3,M
+2MB*?/ !/)3,)/0#G
4/P2M2M)089H2.J
:
-N$=CD""#$ &#G#
D/K#.5+3(2C/0>2>;
'B2M G'#3,#)/@E:
Có thể bạn chưa biết:
#K2,3N#)
Cl#) ;.#$l#)*.G)CN:
1. #7•`S…nSS`%
;AnSS`$;#7•FNG
#.57#
!C#$/K5
!u3/K5(
Bu[-=$#)7#
;
Cu%:C#7•*#$=B'#$-
/)CB/K5$#N/Ns=$3
4$#$:e$+GFK--/K5<
_7`R
Đề Án : Mạng máy nh, Internet, Virus
C3A'N !u5a3 /)B
u$#7•[) a,7#KQ--aD/K
5#7•%:
2. g˜Zg#7…g227`…nSSx%
g˜Zg#7I#$g227ND$B)ji
g˜Z$3 !B$,<) K!XXg;!C
:QW$2END$77MCg#73,.D

Š:jH J.#$#)E
4#>2($@;
+C,C:
g7D#.57#$ !#hB
K!ZgguggU Vt_œZ#g7
ug/7g77%,#
:3L7#.57#
4D:0B#)
$*/K/"$/K2)Jn`
ji0nlS:SSSfgXN2D#)$:
5. gU_7…LV%`…nSS‹%
_C/0MCBgU#.57#;C€nxS 7 
/7o27• 
/,,BgU !
C ,.-
Ebr:QY 4
jX=6#7 |7#
<[/K 5
$<$=/7ƒ3 , 5 $
,,ND B:
\$RAnSS‹4 CN30w
`z`SG*/K 5gU$$
$3, 5 $/K ,,-GND
XXpgƒw4 K!:g
UY3#EK
G;nST#g2o#C+;$/K5g*
 J,NDB4g2:
_7n`
Đề Án : Mạng máy nh, Internet, Virus
_7nn