Andreas C stumbled upon what might possibly be the most secure code ever written. At least, according to its original author.

Following is the contents of just one of many similarly coded PHP pages...

<?PHP session_start();
$str = 'PD9waHAgc2Vzc2lvbl9zdGFydCgpOyAgDQoNCi8vL01BSUxQRVJNSU4vLy8NCmlmIChpc3NldCgkX1NFU1
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ltZSgpOw0KICAkczMzMzdGNzMzQTQzMjg3NjdVNTE1NUE3NTFBNjEzMDU0OXgzODQySzczOEE0ODI5MjYyID0gDQog
ICAgYWJzKCRfU0VTU0lPTlsneDYxMFk3MDZBMTYyNjA5NGhTNDk1M1c3NDlBNTkzMDM1MVo2NDY4TDc2NEE3NDMxOD
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OEE1ODMwMjUyJ10pOyANCg0KICAkejMyMzZUNzMyQTQyMjg2Njh1NDM0N1o3NDNBNTMyOTc1N3g0NjUwUzc0NkE1Nj
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kzaiddID49IDIwKSAgDQogICAgICAgJiYgKCRzMzMzN0Y3MzNBNDMyODc2N1U1MTU1QTc1MUE2MTMwNTQ5eDM4NDJL
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NTBTNzQ2QTU2MzAwNTQ7DQogICAgZWNobyAieW91IGhhdmUgZXhjZWVkZWQgdGhlIG51bWJlciBvZiB0aW1lcyB5b3
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KCk7IA0KICAgICRfU0VTU0lPTlsnczE3MjFVNzE3QTI3MjcxODN0MjZENzAyYTEyMjYwMTk4eHk3MTFUNzA3QTE3Mj
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M0N1o3NDNBNTMyOTc1N3g0NjUwUzc0NkE1NjMwMDU0ID4gMikgew0KICAgICRfU0VTU0lPTlsneDIyMjZENzIyQTMy
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kJCQkJCQkJCQkvLy9NQUlMUEVSTUlOLy8vDQoNCiRpZF9oZCA9ICc4OEJCLTU4MjInOw0KJGlkX251bSA9ICdmZ2ho
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bCAoJyA/PicgLiAkWTU1NTlVNzU1QTY1MzA5NDV3MjkzM0g3MjlBMzkyODM3MXY0OEg3MDRBMTQyNjAzOTZ3IC4gJz
w/cGhwICcpOw0KICBmY2xvc2UoJFk2MzY3Szc2M0E3MzMxNzM3Vzg1ODlCNzg1QTk1MzM5MTVVOTE5NU83OTFBMTAx
MzQ1MSk7DQp9DQoNCmlmICgoJGdvdHRlbiA9PSAxMTEpJiYoJGhkID09ICRpZF9oZCApKSB7DQogIGluY2x1ZGUgKC
dpbml0cm9kZUdsb2JhbF9jb20ucGhwJyk7DQp9IA0KZWxzZWlmICgkZ290dGVuICE9IDExMSkgeyANCiAgaW5jbHVk
ZSAoJ2luaXRyb2RlR2xvYmFsX2NvbS5waHAnKTsNCn0gDQplbHNlaWYgKCgkZ290dGVuID09IDExMSkmJigkaGQgIT
0gJGlkX2hkICkpIHsNCiAgZWNobyAkZXJyb3JfbXNnOw0KfSANCj8+'; $str2 = base64_decode($str); /* echo '<pre>'.$str2.'</pre>'; */ /* exit(); */ eval (' ?' . '>' .$str2 . '<' . '?php ');?>

 

Of course, base-64 encoding was not the original coder’s only line of defense. Just in case a clever hacker gained access to the server containing the PHP code files, and figured out how to decode base-64, the hacker would likely hit a wall against these impossibly-long variable names in the decoded code...

///MAILPERMIN///
if (isset($_SESSION['z812F708A1826292fS6569P765A7531935z4852E748A5830252'])) {
  $_SESSION['x610Y706A1626094hS4953W749A5930351Z6468L764A7431836'] = time();
  $s3337F733A4328767U5155A751A6130549x3842K738A4829262 = 
    abs($_SESSION['x610Y706A1626094hS4953W749A5930351Z6468L764A7431836'] 
      - $_SESSION['z812F708A1826292fS6569P765A7531935z4852E748A5830252']); 
  
  $z3236T732A4228668u4347Z743A5329757x4650S746A5630054 
    = $s3337F733A4328767U5155A751A6130549x3842K738A4829262 / 60;
  
  if ( ($_SESSION['s1721U717A2727183t26D702a12260198xy711T707A1726193j'] >= 20)  
       && ($s3337F733A4328767U5155A751A6130549x3842K738A4829262 <= 30* 60 )) {
    $z3236T732A4228668u4347Z743A5329757x4650S746A5630054 
      = 30 * 60 - $z3236T732A4228668u4347Z743A5329757x4650S746A5630054;
    echo "you have exceeded the number of times you are allowed to use this form
          <br><br>Please try again in an one (1)hour or three(3)<br>";
    exit;
  
  ...

 

Of course, the full code is certainly worthwhile checking out. So, hackers, go forth and decode.

As for what this super-secret-sensitive page was used for... it was a “Contact Us” form.