Local File Inclusion in CMS Source

Vulnerability ID: HTB22552
Reference: http://www.htbridge.ch/advisory/local_file_inclusion_in_cms_source_1.html
Product: CMS Source
Vendor: Proud Daddy Web Design ( http://www.prouddaddy.net/ )
Vulnerable Version: Current at 28.07.2010 and Probably Prior Versions
Vendor Notification: 28 July 2010
Vulnerability Type: Local File Inclusion
Status: Not Fixed, Vendor Alerted, Awaiting Vendor Response
Risk level: High
Credit: High-Tech Bridge SA - Ethical Hacking & Penetration Testing (http://www.htbridge.ch/)

Vulnerability Details:
Null-byte (%00) injection and catalog bypass (…/) attacks are possible and can lead to arbitrary local file inclusion and execution. An attacker needs to have a possibility to modify or create local files to exploit this vulnerability, or have a malicious file already existing in the system.

The vulnerability exists due to failure in the "manage.php" script to properly sanitize user-supplied input in "target" variable. An attacker can compromise the application, execute arbitrary operating system commands, alter file system integrity, access or modify sensitive data.

Attacker can use browser to exploit this vulnerability. The following PoC is available:

http://host/home/demo1/manage.php?target=./../../../../../../../../../../../../etc/passwd%00
http://host/home/demo1/manage.php?target=./../../../../../../../../../../../../path/to/php_file%00