Apple macOS/iOS - 'CAMediaTimingFunctionBuiltin' NSKeyedArchiver Memory Corruption Due to Lack of Bounds Checking

Author: Google Security Research
type: dos
platform: multiple
port: 
date_added: 2017-05-23 
date_updated: 2017-12-16 
verified: 1 
codes: CVE-2017-2527;HT207797 
tags: 
aliases:  
screenshot_url:  
application_url: 

Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1175

CAMediaTimingFunctionBuiltin is a class in QuartzCore. Its initWithCoder: method
reads an Int "index" then passes that to builtin_function

  mov     ebx, edi <-- controlled unsigned int
  mov     r14d, ebx
  lea     r15, __ZL9functions_0 ; functions
  mov     rax, [r15+r14*8]

if rax is non-null it's returned as an objective-c object pointer and the objective-c retain
selector is sent to it.

Serialized poc in attached file with an index of 12345678.

tested on MacOS 10.12.3 (16D32)


Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/42052.zip