Rowhammer – NaCl Sandbox Escape

  • 作者: Google Security Research
    日期: 2015-03-09
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/36311/
  • Sources:
    http://googleprojectzero.blogspot.ca/2015/03/exploiting-dram-rowhammer-bug-to-gain.html
    https://code.google.com/p/google-security-research/issues/detail?id=284
    
    Full PoC: https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/36311.tar.gz
    
    
    This is a proof-of-concept exploit that is able to escape from Native
    Client's x86-64 sandbox on machines that are susceptible to the DRAM
    "rowhammer" problem.It works by inducing a bit flip in read-only
    code so that the code is no longer safe, producing instruction
    sequences that wouldn't pass NaCl's x86-64 validator.
    
    Note that this uses the CLFLUSH instruction, so it doesn't work in
    newer versions of NaCl where this instruction is disallowed by the
    validator.
    
    There are two ways to test the exploit program without getting a real
    rowhammer-induced bit flip:
    
     * Unit testing: rowhammer_escape_test.c can be compiled and run as a
     Linux executable (instead of as a NaCl executable).In this case,
     it tests each possible bit flip in its code template, checking that
     each is handled correctly.
    
     * Testing inside NaCl: The patch "inject_bit_flip_for_testing.patch"
     modifies NaCl's dyncode_create() syscall to inject a bit flip for
     testing purposes.This syscall is NaCl's interface for loading
     code dynamically.
    
    Mark Seaborn
    mseaborn@chromium.org
    March 2015