 .       -
     .

    Red Hat Linux     MD5 (.
),   ,  ,  
DES (. ).    ,    -
,      .

,       ,    
 ,    .      (  , 
  ),  ,    ,  
 .       , -
   -  (, ),     
   .   ,        
,    C&yGramS (candygrams).     
  ASCII,     .

        -
,   ,   .   -
,     , ,      -
.      ,  ,
,    .  , 
    crack  cops.       , -
  ,    CERT (www.cert.org)  , 
  computer emergency response team (  
).     www. cert. org/tech_tips.

,  ,  ,      
,  root     setuid (, mail 
su).  ,       , -
   setuid   root,    
 .         
.   ,    setuid-  -
  mount   -nosuid,      
 fstab. .  "fstab:   "  12.

        -
  BIOS,   BIOS   .  -
 BIOS      Security ().   -
 BIOS.    BIOS    . -
 BIOS         .

    root

      root 
postmaster,     .    -
   root  (.  "  "  20),
     root.     -
       root,     -
    su.      root 
 su     root    mail -u root.

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