Adobe Flash – Type Confusion in IExternalizable.readExternal When Performing Local Serialization

  • 作者: Google Security Research
    日期: 2015-12-14
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/38969/
  • Source: https://code.google.com/p/google-security-research/issues/detail?id=548
    
    If IExternalizable.readExternal is overridden with a value that is not a function, Flash assumes it is a function even though it is not one. This leads to execution of a 'method' outside of the ActionScript object's ActionScript vtable, leading to memory corruption.
    
    A sample swf is attached. ActionScript code is also attached, but it does not compile to the needed to swf. To get the PoC, decompress the swf using flasm -x myswf, and then search for "teadExternal" and change it to "readExternal".
    
    
    Proof of Concept:
    https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/38969.zip