Bugzilla Bug 17386

Re: MySQL user can be changed to root 
 
From:  
Sergei Golubchik <serg@mysql.com> 
 
 
To:  
"Guido A.J. Stevens" <gyst@nfg.nl> 
 
 
Date:  
Monday 20.08.38 
 
 
Hi! 
 
Both to bugtraq and mysql list: 
 
This issue has been adressed in 3.23.56 (release build is started 
today), and some steps were taken to alleviate the threat. 
 
In particular, MySQL will no longer read config files that are 
world-writeable (and SELECT ... OUTFILE always creates world-writeable 
files). Also, unlike other options, for --user option the first one will 
have the precedence. So if --user is set in /etc/my.cnf (as it is 
recommended in the manual), datadir/my.cnf will not be able to override 
it. 
 
Fixing this issue in more robust way would mean introducing too big and 
incompatible changes into stable version, thus breaking lots of 
installations. It is to be done in 4.1. 
  
Regards, 
Sergei 
 
On Mar 10, Guido A.J. Stevens wrote: 
>  
> I can confirm this privilege escalation in mysql-server   3.23.49-8.2  
> (debian/stable on linux/i386). Any mysql user with file privileges can  
> trick the mysql server into running as root on restart of the mysql  
> subsystem. 
>  
> bugsman@libero.it wrote: 
>  
> > mysql>SELECT * INTO OUTFILE '/path/to/mysql/datadir/my.cnf' FROM hack 
>  
> > Now, when the mysql server will be restarted, the user option in our 
> > datadir my.cnf will override the one in /etc/my.cnf and mysql server will 
> > run as root 
 
--  
MySQL Development Team 
   __  ___     ___ ____  __ 
  /  |/  /_ __/ __/ __ \/ /   Sergei Golubchik <serg@mysql.com> 
 / /|_/ / // /\ \/ /_/ / /__  MySQL AB, http://www.mysql.com/ 
/_/  /_/\_, /___/\___\_\___/  Osnabrueck, Germany 
       <___/

glsa sent